I recently also just installed the InvisibleShield for my HTC Desire - the maximum coverage protector. It covers the screen, sides, top and bottom, and the back. Almost all parts of my phone are covered and protected, with a few exposed edges here and there.
The InvisibleShield works really well. Installation can be slightly tricky, and takes a long time. It took me over an hour to install mine, but that's just coz I'm a bit of a perfectionist, and like to get it done properly 100% first time around. Take your time, and do it properly the first time around.
You don't spray the liquid onto your phone, you spray it onto the cover, and a bit on your fingers, to make handling the cover easier. Most of the liquid dries up very quickly - it's not that easy to get liquid into your phone. If you do, then you're spraying way too much, or doing something else wrong. Remember to work in a clean dust free environment, for the best results. Remember to also remove your battery, in case liquid does get inside. You don't want to cause electrical damage.
Oh, and about the liquid, my spray bottle came just over half full. So I immediately topped it up with tap water (as per online recommendations). I'd recommend topping up first and using it like that. It will last longer, and is better than topping up an empty bottle once you have run out (which you probably will, depending how full your bottle came, and if you installing just the screen protector, or the maximum coverage protector). The liquid to water concentration will be greater, and you'll want to use the liquid again in the future, so you're covering yourself. Alternatively order an extra bottle of liquid when buying your InvisibleShield.
And don't worry if you still see lots of small air bubbles under the cover. I was a bit worried about this, but they really do disappear after 2-3 days.
It's really cool that the cover is only a few millimeters thick, and provides excellent protection. Gone are the days of big ugly bulky covers. Your phone remains slim and feels great - just how it was intended when designed, but is still very well protected. I now don't mind too much if I have to keep keys in the same pocket as my phone.
Make sure you working in a clean dust free environment to get the best results. And take your time. MAke sure everything is lined up nicely.