How to Make a Keyhole Back Dress Without a Pattern in 5 Simple Steps

JRenee DIY
by JRenee DIY
10 Materials
2 Hours

Looking to make a sexy outfit and not quite sure where to start? I have the perfect DIY for you! In this tutorial, I’ll show you how to make a keyhole back dress from scratch.

I can’t wait to get started and show you just how banging this DIY keyhole dress turns out. Let’s get started.

Tools and materials:

  • Stretchy fabric
  • Ruler
  • Marker or chalk
  • Sewing machine
  • Pins
  • Matching thread
  • A dress that fits
  • Scissors
  • Rotary cutter
  • Curved ruler
Folding the fabric to make the pattern

1. Make the pattern

Right, let’s make the dress sewing pattern with a keyhole back. Start by folding your fabric in half, as shown. The right sides should be facing. 

Tip: Use a very stretchy fabric for this project as it is a bodycon-type dress. 

Tracing an existing dress for the pattern

Take your favorite fitting dress and fold it in half. Align the centerfold of the dress on the folded fabric. This pattern will be for the back piece. 

Tracing the collar

Now, trace out the collar. 

Adding an inch or two of seam allowance

Then, trace the rest of the areas with an inch or two seam allowance. 

Cleaning the curves with a curve ruler

To make clean curves, use curved rulers around the armhole area. This is optional, but it defines your lines better. Also, use this at the neckline seam and all the way around the body of the dress, as needed. 

How to draw a bodycon dress pattern

At the bottom, draw a straight line. Consider making it a little longer for hem allowance. 

Cutting out the fabric

Now cut your pattern with either scissors or a rotary cutter. 

Making the front pattern

Repeat the same for the front of the dress; folding the center and aligning it to the fold of the fabric. Trace out your shape with the same seam allowance used and curve where needed. Then, cut. 

DIY bodycon dress pattern pieces

Here are your two pieces! 

Pinning the dress at the shoulder and side seams, ready to sew

2. Assemble the DIY keyhole dress

Place both pieces right sides together and pin the shoulder and side seams. Ensure that you do not pin the armholes. 

Sewing the pinned areas with a zigzag stitch

Now, sew the pinned areas with a zigzag stitch. Also, sew about ¼ inch away from the edge. After, you can either serge the ends or do another zigzag stitch at the raw edges. 

Amending the neckline

3. Amend the neckline (optional)

I wanted a deeper neckline, so I decided to amend the neckline area. To do this, simply try on the DIY keyhole dress and draw the new neckline accordingly. 

Marking the keyhole back

For the back, mark where the top of the keyhole would be, too. 

Drawing the front neckline with a curved ruler

Redraw the front neckline with a curved ruler. 

Pinning the front to cut the new neckline

Fold the front part in half, and pin the top and center, then cut. Like this, the neckline will be symmetrical. 

How to make a keyhole dress

4. Make the back keyhole

For the back keyhole, start at the mark you drew. Then, draw half a diamond shape. Start with an angled 4-5 inch line. 

Dress sewing pattern with keyhole back

Draw another angled line from the last point. 

Cutting out the keyhole shape

Fold the back part in half and pin the fabric, so it doesn’t move. Then, cut the half diamond shape. 

How to sew a keyhole opening on a dress

5. Hem

Now, we need to hem all the raw edges, including the keyhole.

Hemming the armholes

Let’s start at the armholes. Simply turn the dress right sides in, and do a double hem around both armhole areas. Pin the fold as you go along. 

Tip: This part may take a while but try not to rush it; you want crisp and clean edges! You’ll thank yourself later, trust me. 

Pinning all the raw edges

Ensure that you’ve pinned the armholes, neckline, keyhole, and bottom of the dress. 

Hemming the back keyhole

For the back keyhole, you can roll the raw edge over once. Like this, the keyhole won’t appear too big. 

Tip: Try pivoting at the corners of the keyhole. When you wear the DIY keyhole dress and it stretches, it will round off the edges. 

Sewing the pinned hems

Sew the pinned hems with a straight stitch. 

How to sew a bodycon dress with a keyhole back

See how professional the edges are now? 

Tip: The bottom hem was a little thicker for me, and that’s okay, as long as you’re happy with the length. 

DIY keyhole dress

How to make a keyhole back dress

How to make a keyhole back dress

That’s it! Let’s try this baby on! I love how it looks. This DIY keyhole dress is such a pretty color and a comfy fit.

I hope you enjoyed this tutorial on how to make a keyhole back dress. The back keyhole definitely gives the dress some back action, don’t you think?

What color will you make your DIY keyhole dress in? Let me know in the comments below. 

Suggested materials:
  • Stretchy fabric
  • Ruler
  • Marker or chalk
See all materials

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