I use a condom occasionally - just did so a couple of days ago. I don't like making a mess so I use one if I want to achieve a hands-free cum thrusting against a towel or the bed. I drain it into the toilet then put the empty condom in the garbage - although I suppose it might be possible to clean and re-roll it.
I've always rolled them on while pinching the tip - I've never known any other way. I also half roll / half slide to get them off - I'm not the thickest, but nonetheless thick enough that typical large condoms are just a bit snug.