Introduction
Meet Top-Bra “Mia” — my go-to multi-talent that sewists around the world keep making on repeat. It’s the one I grab when I want a comfy gym crop, a quick swim top, or a light bralette that still feels pretty. With the right fabric, Mia slips from workout to sauna to pool (yes, I literally do that), or pairs with jeans as a casual going-out top. If you haven’t got it yet, here’s the Top-Bra “Mia” sewing pattern.
Mia comes to life in three ways: a double-layer front for extra support (gym & swim), a single-layer for when fabric is tight but you still want that quick make, and a lace scallop-edge version for lingerie vibes. Same pattern, three personalities — you choose your adventure and I’ll walk you through it like we’re sewing together at the table.
Materials & Tools You’ll Need
For gym/swim versions, reach for spandex, Lycra or polyester with four-way stretch — sturdy, supportive, and great when you make the front double-layer. For underwear, I love mesh and lace; lace with a scallop edge turns Mia into a beauty (we’ll keep the scallops visible at the hem). If you’re after cosy lounge wear, a soft jersey works too. And if you want that romantic lingerie look, here’s a handy lace to get you started.
Elastics you’ll actually use. The two heroes here are fold-over elastic (easy, neat) and picot elastic (prettier edge, needs folding). For more under-bust support you can use a wider elastic band; just know it will lengthen the top slightly compared to FOE, which hugs right under the bust for a clean crop finish.
If you’re just starting out or building your toolkit slowly, here’s a list of the cheapest sewing tools that still work great (no budget burnout) to help you get going without spending a fortune.
Straps & hardware, sized smart.
Grab rings/sliders and proper strap elastic. Up to size L → 10 mm strap elastic works well; XL and above → 12 mm feels better for heavier busts. In front you can keep the simple cut-out with a strap, make it adjustable, or even swap to a small chain/connector — completely your choice and very cute.
Thread, needles, and the machines. Use polyester thread and a pack of 75/11 needles — your baseline for stretch fabrics that keeps skipped stitches at bay. You can sew everything on a regular sewing machine (zigzag or elastic stitch); an overlocker is a bonus but not required, especially for the double-layer method where all inner seams are hidden. If you don’t have an overlocker for the single-layer version, use a finishing foot/elastic stitch so raw edges look tidy.
Cutting & marking you’ll actually do. Keep a chalk handy and use pins or clips for delicate lace. Cut with sharp scissors, or go for a rotary cutter on a healing mat if that’s your workflow.
Preparation Tips
Print on A4 and check the 5×5 cm test square first so sizing behaves. Larger sizes come on multiple pages — match the triangle markers (A1+A1), tape together, and you’ll have the full piece; smaller sizes fit on a single page. Seam allowance is already included in the pattern, so there’s no “oh no, I forgot” moment at the cutting stage.
Fold your fabric and place the pattern with the “Fold” line exactly on the fabric fold for both front and back pieces. Transfer strap notches on the back piece — they matter later when you attach straps neatly. For Method 1 you’ll cut one back + two fronts; for Method 2 it’s one back + one front; and for the lace version we’ll talk about scallop placement in its own section.
Method 1: Double-Layer Front Top (supportive & neat insides)
This is the “gym to swim” winner. The double-layer front adds support and hides every inner seam — perfect if you’re sewing on a regular machine and want a spotless finish.
Cut one back and two fronts. Make a little “sandwich”: front piece right-side up, place the back right-side down on top (so front & back are face-to-face), then lay the second front right-side down (so the two front pieces are face-to-face). Align both side seams, pin/clip, and sew both sides. Now deal with the front cut-out arc: move the back piece out of the way, align the two front layers along the arc, and sew the arc only through the two front layers. Flip the whole thing right-side out — your front is now fully lined and seams are hidden like a secret.
Elastic time.
Start by stabilising the front centre cut-out with your chosen elastic — FOE or picot, your call. Then sew elastic around the top edges: from one front strap point, around the back, and back to the other strap point. Leave ~2 cm unsewn at each strap point so you have space to insert rings/straps/chain later. Under-bust finish: either continue with FOE all the way, or switch to a band elastic. For the band method, wrap the band under your bust for comfort, add ~1.5 cm for the join, stitch the ends to form a loop, pin it evenly around the hem, and attach with zigzag/elastic stitch.
Straps your way. Adjustable? Spaghetti? Fabric-matching? Pick what fits your look and use my demo of five different methods how to make the straps to choose. Attach the back ends at the notches, then set the front length to your comfort — tighter for sporty, looser for lounge. Want to sew together with me (and grab fool-proof machine settings)? Watch the Top Mia Sewing Tutorial.
Method 2: Single-Layer Top (fast & fabric-friendly)
When the fabric piece is small or you just want a quick make, the single-layer approach shines.
Cut one back and one front. Place them right-sides together and sew both side seams. If you don’t have an overlocker, use an elastic stitch/finishing foot so those open seam allowances look neat — this version shows insides, so give the edges a little love. Turn right-side out.
Stabilise the front arc with elastic first, then sew elastic along the neckline/armholes from one strap point around the back to the other, again leaving ~2 cm free at each strap point for hardware. At the hem, either keep going with fold-over elastic straight from the roll, or create a band loop like in Method 1 (measure under bust, add ~1.5 cm for the join, stitch into a loop, pin evenly, attach). Finish with your preferred straps (see five methods) and adjust length on the body before locking them in.
This one’s light, quick, and perfect for casual bra tops or a speedy swim solution.
Method 3: Lace Scallop-Edge Bralette (keep those scallops pretty)
For this version we use the lace scallops as the hem. Place the bottom of the pattern slightly above the scallop edge — about 1–1.5 cm higher — so when you add elastic, the decorative edge stays visible and clean. Cut the front and back, transfer strap notches, then sew both side seams.
Press the seam allowances toward the back (golden rule: side seams go toward the back), and topstitch over them with elastic stitch/zigzag to keep them flat and reinforced — especially useful with lace. Now add elastic to the front arc and the upper edges: start at one strap point, go around the back, and finish at the other strap point, leaving your ~2 cm gaps ready for straps/connectors.
At the hem, avoid FOE on the scallops. Use a slim ~1 cm elastic (or picot elastic) sewn just above the scallop line so the lace edge stays free and beautiful. Keep the elastic straight so it doesn’t peek through the low parts of each scallop. This version is strictly decorative-edge friendly, so don’t use a wide waistband elastic here — we want that scallop to shine.
Strap styling. Back-attached adjustable straps are classic; fabric spaghetti straps are lovely; or try a halter idea: attach at the back, thread through front rings, then tie behind your neck for an adjustable look without hardware. Front centre can host a small chain or jewellery connector if you like.
Sizing tip for lace:
Lace (especially nylon lace) stretches less than mesh, Lycra or polyester four-way stretch. If your perfect fit in four-way stretch is XL, then in lace cut one size up (XXL) for this pattern so it sits properly and doesn’t squeeze.
This “one-size-up-in-lace” rule applies across most underwear patterns not specifically drafted for lace, especially any design with side seams (bras, bralettes, knickers). The exception: pieces with adjustable straps (e.g., knickers with adjustable sides) — those straps can compensate for stretch, so sizing up isn’t necessary there.
Fitting & Adjustments
Elastic rule #1: never pre-cut elastic. Sew from the roll and trim at the end. Elastic quality varies — some are loose and stretchy, others are rigid — so pre-cutting just leads to cursing and unpicking. Stretch the elastic slightly, never the fabric, and keep that stretch even all the way around.
Strap calibration matters. Attach the backs at the notches first, try the top on, thread fronts through rings, and set the length on your body. Lock the length only when you’re happy — especially if you’re making non-adjustable straight straps.
Alternate front option. If you’d like a second design from the same pattern, skip the arc cut-out and draw a straight line across the front hem area. You’ll get a full-coverage front — clean, simple, and very wearable.
Finishing Touches
Snip stray threads, tidy the elastic starts/ends, and give the seams a firm finger-press. If you left those little 2 cm gaps at the strap points and front centre, this is the moment to add rings, sliders, or a small chain/connector and stitch them securely with a neat zigzag.
Now style it: gym to swim (swap leggings for bikini bottoms and off you go), loungewear in jersey, or casual top with jeans and a cardigan. Mia’s far too cute to stay hidden.
Final Thoughts
Three methods, one pattern — and a top you’ll actually wear. I can’t wait to see your version: supportive double-layer, speedy single-layer, or that romantic scallop lace. If you’re sewing along, keep my Top Mia Sewing Tutorial open for settings and step-by-step. And when you’re ready for your next make, browse my full collection of underwear sewing patterns.
