I usually apply with a brush. I usually use on flat surfaces.

I've taken plain wooden boxes and painted and decoupaged them. I've taken clear glass plates and decoupage on the back so the pattern shows through from the front...for decoration only, not eating.

I've decoupaged on the front of furniture to decorate painted thrift store finds.

I've taken cheap vases and decoupage the exterior and then streaked it roughly with rub n buff for an antiqued look.

I've spent lots of time in front of the TV cutting out interesting things from decorating magazines to use for decoupage, like birds, columns, statues, etc. Good for keeping the hands busy. You can also get wallpaper books for free that are discontinued and decouapge the wallpaper cutouts.

Im working on a project now Im using paper birch bark to cover picture frame for hubbys new office.He goes on big game hunts so I thought this would be neat on a photo frame.
I did a frame once where I covered the matt with a map of where he was on that hunt,He can look at it and say oh this is when I was in colorado,neat.

I saw someone once who did beautiful decoupage using onion skins. Delicate and amazing and a high degree of patience required.

There are some amazing examples on Pinterest if you ever want some inspiration - it inspired me to have a go at my very own mod podge plant pot (not the greatest lol)

http://www.the-chic-boutique.co.uk/time-mod-podge-life-plant-pots/

Here is a link that might be useful: plant pot mod podge

One of my favorite things is my queen amidala lamp, I used qa paper dolls.
I used to decoupage a lot, but have switched to mosaics because decoupage fades in the sun and can't hold color outdoors, even on a porch.
Kathy

Here's a blog you might like. I ran across it a few days ago.
http://modpodgerocksblog.com/