This is a very quick, simple, cheap, non-invasive way to support your ukulele while playing. You do not need to drill your uke, so it is especially suitable for small cheap instruments with no tail block to support a drilled button.
Unlike some other designs, it does not obscure the soundhole, nor does it hang the weight of the ukulele on a clip or hook that could damage the edge of the soundhole and get in the way of your playing.
You will need:
Bulky yarn or shoelaces, string, cord, or ribbon.
Note on materials:
You can use anything that is long enough and strong enough to support the weight of your uke. I used a few meters of Rico Cancan yarn left over from making a scarf, which is thick and soft and pretty, but you could also make your own cord by crochet, French knitting, braiding etc, if you are less lazy than me. You could also choose to use a different material for the actual strap - I thought of using some of the useless fabric belts that sometimes come with new trousers, but decided to use more of the same yarn.
Step 1: Cut Yarn
Cut a piece of yarn 5 or 6 times longer than the body of your instrument. In my case, the uke is 23cm long and I cut 137cm. Slightly longer might have been a bit less fiddly.
Step 2: Form a Noose
Fold the yarn in half, and make a slip knot about halfway along the doubled length.
Step 3: Put It Around the Uke
Slip the large loop over your uke, with the loop behind the heel joining the neck to the body. The front will look like this.
Step 4: Tie It Tight.
Turn your uke over, and tie the loose ends to the loop behind the heel. Pull it quite tight. It will look like this.
Step 5: Adjust Slip Knot
The slip knot is at the end where a strap button would be. If you don't like the precise position you can fiddle with it slightly, as a slip knot can easily be tightened or loosened.
Step 6: Cut Cross Piece of Yarn
Cut a piece of yarn long enough to wrap twice around the waist of your ukulele. Mine was about 77cm.
Step 7: Tie Cross Yarn to Lengthwise Yarn
Tie the new yarn around the yarn at the back of the ukulele, at the mid-point of the new yarn, and in line with the waist and soundhole of the ukulele.
Step 8: Attach at Front of Uke
Tuck the ends of the new piece of yarn behind the yarn at the front of the uke.
Step 9: Create a Diamond
Pull the ends so that the yarn at the front forms a diamond, with the corners at the edge of the uke, at the waist.
Step 10: Secure Cross-yarn on Back
Tie cross-yarn to the lengthwise yarn at the back of the ukulele.
Step 11: Cut a Yarn Strap
Cut a piece of yarn slightly more than double the length you want your finished strap to be. Mine was about 2.3m.
Step 12: Attach Strap to Headstock
Attach it around your headstock, under the strings, and behind the nut, at the midpoint of the strap yarn. Tie ends together with a simple knot to form a reasonably snug loop.
Step 13: Tie Other End
Securely tie the other ends to the yarn at the other end of the ukulele. I used three half hitches.