It’s not as scary as it looks to do yourself
The worst that happens is that you hit the quick and there’s some bleeding, but it’s easily fixed if you have some styptic powder or cornstarch nearby to dunk the nail in. Then you leave the next nail longer
If you start by just nipping off teeny tiny pieces from the ends, you can eventually get a feel for what the nail should look like and how long they should be- it’s also really unlikely that you’ll cause damage trimming just the very tips off. Also make sure you’re comfortable with the kind of trimmers you’re using, there are many styles out there. I prefer a dog-size clipper of this general style: http://www.petsmart.com/product/index.jsp?productId=2750651 because I’ve used them the most, but other people prefer small cat-nail trimmers or “guillotine”-style trimmers. Whatever you’re most comfortable with!
I usually trim my buns’ nails when I start to see them peeking out from the fluff on their feet, every month to two months as needed. Or, when the cat needs her nails done and I go on a clipping binge
(they’re on more or less the same schedule)