I love this swim suit for a few reasons: it's easy to sew, inexpensive, and practical. Last year my toddler had a one piece, and it was all fun and games until I had to pry it off her to change her diaper. A two piece is just more sensible to wear for their diaper loving bums. And because this swim suit is easy and cheap to construct, I'll be making a couple more versions as she grows.

A quick word on the swim bottoms: I despise sewing elastic casings for the legs on diaper covers or bikini bottoms, so I make shorts instead. They are much easier to make, and these are so short they almost look like a diaper cover. Take that lame leg casings! And if you're in a hurry and don't have time to sew the shorts, skip it. Just slip on a swim diaper with some plastic shorts and she'll be just as happy. Most pools require that anyway.

So, here's the supplies:

Two 10"x15" pieces of Swim Fabric for the top
Two 10"x 5 1/2" pieces of Swim Fabric for the bottom
Two 15"x2" pieces of Swim Fabric for the ties
Two 10" pieces of 1/4" elastic
17" of 3/4" elastic
matching thread
rotary cutter and mat

Fits size 12m to 2T

Step 1: Swim Suit Bodice

To make the bodice (1) cut two pieces, (2) serge the sides of the pieces together, (3) hem the top of the piece and then (4) gather (or ruche) the sides.

Swim Suit Bodice

Cut two pieces of swim suit fabric to measure 10"x15" each. Serge the tops for a finished look.
With right sides together (laying the right side of one piece on top of the right side of the other), align the sides and serge or sew them together.
Fold the top edge over 1/2" and hem the top. Hem right along the serged edge.
Turn the suit inside out and gather the sides of the swim suit. You'll do this by sewing and pulling a 10" piece of 1/4" elastic to each side of the swim suit, until you reach the bottom. Cut off the excess elastic if you have any. I like a tight gather, so I had about an inch that was cut off.

TIP: Don't pull too tight as you sew the elastic. Pull the elastic about an inch down while sewing for a good gather.

Step 2: Cut and Attach Ties

Cut two pieces of fabric to measure 15"x2". Fold the fabric in half lengthwise, then fold in half again. Sew along the long edge of the piece, with the fold on the other long side.

Attaching Ties

Measure 3" in from each side on the top of the swim suit and pin the tie to the inside of the suit. Attach the tie to the suit by sewing along the hemmed line, making sure to sew right along the hem line. Next, turn the suit right side out (if it wasn't) and top stitch around the whole suit- close to the edge of the top of the suit. Your tie should be tacked down at the hem and now the top stitch when finished.

Step 3: Adding Bows

Cut a long thin strip of scrap material (1/4" to 1/2" wide and 18" long or so) along the selvage edge to make some bows. Once cut, pull the strip to curl the fabric. If you cut the material a different way, the material curls the wrong way, so make sure it curls correctly by cutting it along the long selvage edge.

Cut the long curled piece of material into 4 small pieces and form little bows. Attach 2 bows to the top where the ties are attached, and 2 more bows to each side on the bottom of ruching on the swim suit.

Step 4: Swim Shorts

Cut two pieces of swim fabric to measure 10" x 5 1/2" each. Cut your material so one 10" side is on the fold, or folded over. Cut the crotch piece out. Measure 1" in from the corner and cut a curve over to two inches high (see picture).
Serge the top of each piece.
With right sides together, serge the crotch together. Repeat for the other piece.
Turn one of the pieces right side out.
With one piece right side out, slip it inside the other pice, matching the edges and crotch seams.
Serge together the two pieces, from the top of the shorts all the way around to the other side.
Turn your shorts right side out and line them up with your rotary cutter to cut them shorter.
Cut them at an angle starting from 1" from the bottom then cutting to 3" up on the side.

Step 5: Elastic Waist and Hem

Create an elastic casing for your shorts. If you've never done this, here are some basic instructions:

Folding the top of the shorts over about 1 1/2".
Sew around the edge, making sure to leave a 1" opening for your elastic.
Thread your 17" piece of 3/4" elastic through the opening and then around the shorts.
When you come back to the beginning, pull your elastic out and tack the front of the elastic with the end of the elastic.
Sew the one inch opening shut.

Finish your shorts by hemming the bottom of each leg over about 1/2".