Yes, yes, I know that they have paint poles for sale in Home Depot. However, a number of them are expensive, plus it is always much more fun to build your own for a much lower price.
1. PVC pipe or 1x2 lumber (I used a long blue plastic tube I found on the street in Manhattan that I believe was used for framing a convention booth)
2. Paint roller
3. Cable ties
4. String (also consider paracord; I probably should have used this for strength purposes)
5. Rubber bands
6. Duct tape
1. First use the duct tape to tape the roller handle to the pole. Make sure it is secure and straight.
2. Use multiple cable ties to firmly secure it to the pole. Perhaps 8 to 10. Cut the ends off.
3. Make a tension loop like shown above and pull it tight around the pole and roller handle. Make sure you go in between the cable ties.
4. Pull it tight, then loop it around the pole/handle several times, keeping the tension high on the rope.
5. Tie it tightly to itself at the end.
6. Optional: Use the rubber bands to further secure the roller to the handle, by looping them over the roller and back down onto the handle. Make sure they go between the cable ties.
7. Use duct tape to cover the ends of the cable ties since they are sharp.