I do it because I've always had an anal fetish, and in the last few years I've had the time and the income to indulge it - to the point where I'm now taking the Rabbit XXXL all the way down to almost the base, as well as the Prince Charming XXXL and the Boss Hogg XXXL halfway down (all mrhankeys).
I get the weekends free to do things, so here's what I do.
I take a shower and use an enema shower head on low to flush things out. I've been doing this for years, so I'm acutely attuned to when things might be up just high enough that it drops while I'm playing, so sometimes this can take up to a half-hour. I usually don't go much past the sigmoid anymore; I used to fill all the way up because the sensation of being filled with water is nice, but it takes so long to flush out when doing it that I stopped that.
I have 2 footstools - one 10 inches tall, the other 14 inches tall. I drape play towels over them and use them as platforms. I usually put a shorter toy on the taller platform. Every now and then I'll break out one of my older, smaller toys, which I can still do by hand. But the newer, bigger toys are 5+ pounds, so that's impractical.
I bounce for hours. I usually start early in the morning, get cleaned and set up, and then proceed to put on some porn or some hard techno. Then I'll go back and forth between the toys I have out, as desired. Every 90 minutes or so, I'll take a break.
When I'm done, I'll pack things up, putting filthy towels in the wash for later. Then I take a quick shower just to wash the lube off of my legs, my butt, and my balls (it's sticky).
It's relaxing and liberating at the same time, as well as feeling OH SO GOOD.