Here are some useful threads that helped me grasp the concept:
My homemade vacuum hanger
Successful DIY SuckXtender
Penimaster SuckXtender (posts with pictures: #26, #27, #28, #71)
You can find more by searching for "vacuum hanger" and "suckxtender".
But it’s really simple to build:
1. Cut off a finger from rubber glove (preferable bigger size, otherwise it likely won’t fit the penis) and cut the finger tip off.
2. Attach it to deodorant cap (which should be a bit bigger than your flaccid).
3. Fasten a cable tie to secure the "sleeve" on the cap. (Note that single cable tie can be used multiple times. You can unhook it using a small screwdriver or similar item.)
4. Add packing tape in shape of letter U which serves as attachment for S hook with weights.
Refer to picture of my hanger posted earlier for easier visualization.
Attaching:
1. Roll the sleeve down like a condom and stretch it over the cap so you can fit your glans in.
2. Glans ridge should be in plane with cap edge, i.e. don’t put your glans all the way in, but just enough so that cap fully covers it.
3. Pull the rolled sleeve from the edge of the cap so it grasps your penis. Once it does, the sleeve should be still unrolled. This can pinch a little.
4. Use your finger to pull out all of excess skin from under the sleeve until only your glans remains in.
5. Unroll the sleeve.
Removing is simple, just roll up the sleeve and use your fingers to pull the glans out of the cap bit by bit.
That’s pretty much it. :) After few sessions of practicing it takes no more than 30 seconds to put on or off.