I use Lexol cleaner. It comes in an orange spray bottle and it's a gel. You put it on a cloth or sponge and clean the saddle/bridle/boots all over and then rinse the sponge and wipe it off with water.
Here's what the bottle looks like: http://www.sewellpartsonline.com/ima...uct/203678.JPG
Then, I take Passier Lederbalsam http://img.smartpak.com/product/lederbalsam.gif
, which is a conditioner. I put it on a different sponge and rub it on, you may have to wipe the excess off if there is any. Usually my tack soaks it up.
For tall boots, I just use boot polish with conditioner in it.
I usually clean my tack about every two weeks, depending on how dirty it is or how brittle it feels. It can go longer without it but seeing as I'm broke, I would like to keep my things in good repair :)
Oh and one more thing about bridles, you should probably soak the bit in hot water every once in a while when you get a bunch of stuff dried onto it like grass and grain. The hot water makes it ALOT easier to wipe off and your horse will thank you!