Tutorial: Sporty knit slip

I’m so in love with this slip, you guys!

Sporty knit slip tutorial - finished | Bicitoro bikes and crafts

I have an army of camisoles that I wear under everything from tees to dresses in order to smooth out bra lines and add a bit of smoothing, etc. (You know.) The problem with wearing a camisole under a dress is that it tends to bunch up around the hips, giving you that weird bulging line right where you least want it.

This sporty knit slip is basically a long tank top, and eliminates that tank-top line problem.

Why is it sporty? It’s made out of wicking, anti-microbial activewear fabric. It’s stretchy, so there’s no problem pedaling, yet it fits a bit snugly, so if your skirt flares up on your bike you’re not giving the world a show. I think it’s quite nice to wear under a dress if I’m pedaling around town.

It’s meant to hug the body snugly, which is why I’m not going to model it for the internet. I’ll let Little Red take on that responsibility, because she doesn’t mind spending a February afternoon standing around in the backyard in her underpinnings. She’s a bit of an exhibitionist that way.

Sporty knit slip tutorial - front view | Bicitoro bikes and crafts

You’ll just have to believe me when I say it looks fabulous on me, too. 🙂

Make your own sporty knit slip

Grab a favorite close-fitting knit camisole – this is your main pattern. The only other pattern piece you need is this one, for the bodice. That piece is for a size small – I’ll talk about modifying it in a moment.

Lay the camisole out on a double layer of knit fabric, and trace around the whole thing with chalk. Use the back of the camisole as your guide, and don’t bother tracing the front at this point. You’ll be making the bodice cups separately.

Figure out where the hem of the camisole hits on your body, and figure out how long you want the slip to be. Draw a line straight down from the camisole’s hem to lengthen the skirt.

(You can make the skirt flare if you like, but I kept it as a pencil silhouette.)

Add seam allowance (I used 1/2″), then cut out the whole thing through both layers.

You now have two Back pieces.

To make one of them into the Front, figure out where the underbust line is. Draw straight across that, add seam allowance, and then cut across.

The bodice cups

Using this pattern piece modified for your own size, cut out two cups.

This piece is designed for a 14″ underbust measurement (flat measured on the Front pattern piece, including seam allowance). It fits well from cup sizes A-C, since the knit material is so stretchy, and it’s designed to fit quite snugly for extra support. I’m a C cup, and it fits great. Little Red’s an A cup, and it looks nice on her, too.

Sporty knit slip tutorial - little red1 | Bicitoro bikes and crafts

That said, if you’re a D or larger (or if you just want more coverage) you should probably do a FBA. (This post on Pattern Scissors Cloth about doing a FBA for the Ruby Slip is a good place to start.)

For a totally effective, totally hack way to modify it to a bigger (or smaller) ribcage size:

Measure flat across the underbust seam of your Front pattern piece (for me, that’s 14″). The lower edge of the cup piece should be two thirds that length when measured at the seam line, subtracting the fullness of the dart (the sample pattern piece is 9.5″ across, subtracting the dart).

Simply blow up that pattern piece on your computer to get the desired dimensions.

Like I said, that’s the totally not tailor’s-union approved way of going up a size. Knit fabric is super forgiving and the cups don’t take up much fabric, so give yourself permission to play around.


Stitch the darts in the cups.

Apply picot lingerie elastic or fold over elastic (I got mine from Porcelynne on Etsy) to the neckline of both cup pieces, leaving a tail long enough to be a strap. (Measure the straps of your pattern camisole to get an idea of length.)

To learn how to use picot elastic, check out this post at Indigorchid. (That’s a great place to start if you want to make your own undies, too.) Angry Chicken has a nice video tutorial on fold over elastic.

Sporty knit slip tutorial - closeup | Bicitoro bikes and crafts

Lay both cups over the pattern to figure out how much they should overlap in front, then baste together.

Stitch the cups to the front of the slip with right sides facing.

Sporty knit slip tutorial - bodice | Bicitoro bikes and crafts

Stitch the front and back together at the side seams.

For all the seams, I used a narrow zigzag stitch, and then finished the edges with my serger.


Now you’ll use the fold over elastic to finish not only the back and underarm, but also the picot elastic straps. This creates a really strong, stretchy strap.

Starting at one end of the picot lingerie lace that edges the neckline, head down under the arm, around the back, and back up the other strap.

Sporty knit slip tutorial - strap detail | Bicitoro bikes and crafts

I use a zigzag stitch down the middle of one edge while the fold over elastic is laying flat. Then I fold it over and zigzag closer to the edge to make it lie neatly. Don’t stretch too much, since your pattern should already be quite snug.

Try on the slip. Pin the straps at the correct length, and mark the hemline. Mine falls about 3″ above my knees.

Stitch the straps in place with a zigzag stitch, and trim off any extra.

Hem the bottom, being sure to use a stretchy stitch, since it’ll stretch quite a bit when you walk or pedal.

Sporty knit slip tutorial - bodice detail | Bicitoro bikes and crafts

That’s it! This project took me about 2 hours, including the time I took to re-do the picot trim because it was wonky at first.

Questions? Ask away in the comments. My goal is to help people be more comfortable sewing quick projects like this without patterns, so I’m happy to help if you get stuck on any of the steps.

3 thoughts on “Tutorial: Sporty knit slip

  1. Oh – I like this!! I might have to try it! I am ALWAYS wearing a tank top to cover my bra straps & sjirts that are a little short for my 6′ frame.

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