This solution is very similar to the other DIY R-Straps on this site. The one distinction is that I believe this is safer.
The other DIY R-Strap examples found here are awesome. Carrying your camera with the standard issue camera strap around one's neck is uncomfortable and unwieldy. So when I started using the R-Straps listed here, I was thrilled with the comfort. However, securing my beloved SLR via a screw in the tripod mount always seemed unsafe while hiking about. What if it unscrewed when I didn't notice? Disclaimer: it never DID come unscrewed, so perhaps I shouldn't complain. However, this is a more secure version of the strap based on a similar premise.
This solution has advantages over tripod mounted solutions in three ways:
1: It's safer. Nothing can come unscrewed and allow your SLR to crash to the floor
2: Your camera can be mounted on a tripod without first removing the strap.
3: You camera can sit flat on a table while the strap is installed.
Step 1: Tried-and-true Connector
This is the spot where people have connected a strap to their camera for years. Let's use it.
Step 2: Tool: Razor Scraper
You can use this to cut the nylon. Heat with a lighter so it cauterizes the cut as you go.
Step 3: Tools / Parts: Grommets
You'll need to get a grommet and the tool to set the grommet. You can find the 1 inch grommets at most hardware stores. However, these are usually brass in color. I prefer the silver colored, and I had to find those in a leather store (Tandy Leather in the bay area).
The right-most tool in the picture is the "punch" which cleanly punches a whole in the wide part of the camera strap for the center of the grommet to fit. I didn't cauterize the inside of the punched hole, though you could. I think the grommet holds it plenty secure from fraying.
Step 4: Camera Strap.
Start with your existing camera strap. And mold it to your desires. Each end of your old camera strap can be used to make a connector for one of these new straps. So make one for a friend, too!
Step 5: Punch a Grommet Hole
I chose to punch the hole for the grommet before cutting the strap so I was sure to have the right amount of space. Measure with the grommet ring in place. Use a hammer to punch it out. Careful, as it will mar the table beneath it. Use a piece of scrap wood, if you like.
Step 6: Hammer in the Grommet
Place the male end of the grommet through the hole. Then place the female part of the grommet over the male end. Then, using the punch that comes with the kit, hammer it into place.
Step 7: Trim the Strap to Size
Here's where you heat the razor blade with a lighter and cut / cauterize the cuts you make on the straps.
Notice there is a leather connection sewn between the skinny trap and the fat strap. You will cut the fat strap part approximately 1 1/4 inch away from the leather connector. They you'll cut the skinny strap approximately 5 3/4 inches away from the leather connector.
You will need to "cauterize" the cut so the nylon does not fray. One way to do this is the cut with scissors and then melt with a lighter. Another way is to heat a knife (or razor blade) with a lighter, and cut with the hot blade. This cauterizes the cut as you go and looks very clean.
Step 8: The Piece Is Complete!
This is about what the finished product should look like.
Step 9: Thread the Skinny Strap Onto the Camera
So now you thread the skinny part either onto the left or right mount point on the camera. I chose the left side so it didn't get in my way when I grabbed it with my right to shoot. You choose!
Now just get a strap with clips at each end (like from a messenger bag). Buy a clip at any hardware store and you're done.
I adjust the strap so the camera is right about at my hip. And I point the lens backward as it hangs. This makes it comfortable as it sits there.