People install gutter guards for a lot of reasons, but safety should be near the top of the list. As we mentioned earlier, if you have clogged gutters, the only way to clear them is to get up on a ladder and remove the debris (or to hire someone to do it for you). If they're working properly, gutter guards should at least lower the number of trips you have to make up to the roof, or prevent you from ever having to clean out another gutter again.
That said, practicing good ladder safety while installing your gutter guards is a must. Every year, thousands of people are injured from ladder falls, many of which could be easily prevented. The best way to prevent yourself from a ladder fall is to avoid working on a ladder when you're alone. If you're working on a ladder, either to clean out the gutters or to install new gutter guards, it's a good idea to work with at least one other person so that they can hand things, like the hose or a bucket, up to you. And speaking of buckets, when cleaning out gutters, use an S-hook to hold your bucket, so that both of your hands are free -- and so the bucket doesn't throw you off balance.
When setting up the ladder, it's also a good idea not to lean it up against your gutters, because the weight of the ladder with a person on it can dent -- or worse, crack -- the gutters. If you can't find a place to lean the ladder up against without damaging your gutters, you could try using an A-frame ladder or an articulating ladder that bends over the gutter without damaging it [source: DIY Network]. When you're working on gutters, you'll find yourself getting down and moving the ladder as you circumnavigate the house, don't forget to safely set up the ladder each time you move it!