As you know, I've only had my stoma a couple of weeks, so it's all still new to me, but I've not found this a problem at all.
The stoma nurse told me I could stand or kneel in front of the toilet to empty it, however, for the sole reason that I was feeling so ill from the surgery I didn't want to stand, I took to sitting far back on the loo and emptying it between my legs. It doesn't seem to splash at all? There's often mess around the pouch opening once it's emptied - quite a bit - so I grab a wad of toilet paper, swipe most of it off and drop the toilet paper between my legs straight into the toilet. Then when there's only a little left on the pouch, I get a baby wipe, clean it thoroughly with that, dry it with some more dry toilet paper, and it's done. (And I make generous use of my new lovely smelling air fresheners/deoderisers while I do it.)
I was told I could change the bag every three days, but the insides starts looking a bit manky - or perhaps it's just my imagination, but after two days I feel like I need a clean one and change it.
Of course, you could always do what the nurses in the hospital do - wear disposable gloves. When I was too sick to get out of bed, the nurses would tuck a small sheet of paper - the kind that they put on beds to protect mattresses of incontinent patients - into my knickers to keep them clean, they pin up the end of my nightie with a clothes peg so that only my chest was covered by the nightie, put on their gloves and empty it there on the bed, into a disposable bowl. No mess. (I guess since protecting your modesty isn't an issue when you're on your own, you could just strip off entirely, to ensure that any splashes or spills can be easily washed away.)
I honestly find it so easy - I guess I've been incredibly lucky. BTW I'm using coloplast bags.