Hi. I actually made that myself. The good news is you can too!
Here’s how:
You need to order Apple Watch lugs. Initially I went with space grey but after wearing it I decided black ones would look better with the black rubber, and black clasp.
You can order the lugs either from amazon or Ali Express. They are cheaper on ali express.
Then you need to order the clasp. The one that comes with the rubber band don’t feel so great since the rubber strap is like $2. I order mine from eBay
https://www.ebay.com/itm/20mm-Watch...lassic-/192720401188?var=&hash=item72c0e13020
Then you need to order the rubber strap from ali express. 22mm for the smaller watches and 24mm for the larger ones. They both tapper down to 20mm. I’d order 2 straps just in case there are some defects on them since they are so cheap. I’ve ordered a few and they are on the most part defect free. Also if you mess up and cut it too short you have a spare.
This is where I order it from. These are great as they don’t attract lint or dust or have mould lines. They aren’t silicone but actual rubber. Possibley recycled tyres? I don’t really know lol.
http://s.aliexpress.com/eQNBNjM7
Once you have everything and are ready to assemble the strap. You want to go ahead and cut them to size. Try cutting less so and see how it fits. The clasp has 3 micro adjust holes. You’d want to use the 3rd or second so,you leave yourself room to adjust for the summer when your wrist swells.
You want to cut the end that goes into the side of the clasp without the micro adjustments with a little tail so it’s tucked in when the clasp closed. Basically whe. You cut off the segments. You want to cut close to the segment that’s going to come off. Not the one that stay on the strap.
Once you’ve sized it. You want to go ahead and disassemble the strap from the lugs and clasp and boil the rubber. Boiling the rubber makes it contour to your wrist better. Plus unfortunately the top of the strap is half a mm shorter than it’s suppose to be. That leaves a small gap that shows the spring bar. It’s easy to stretch it to the right size though.
So you want to boil water in a kettle. Place the rubber in a glass or something similar that fits. Pour the water and leave the rubber in the boiling water for 5 minutes.
After 5 minutes take out the straps. Under cold water stretch the top of the strap whilst simultaneously bending the strap in a C shape. After about 20 seconds under the cold water the strap is now ready. It should bounce back to a shape between C and L.
Also you might want to get some good quality spring bars. The ones that come wit the strap might not be too good and might rust if you take your watch into the water.
Also when installing the strap into the lugs it’s a tight fit so try not to scratch the lugs. Maybe put some masking tape on it.
Well there you go. Hope that helps.