The Midas Touch hand thing is much, much simpler than you think it is. It was just done by revealing a gold hand layer with a mask. The gold hand looks like it was created with clever use of Colorama on the same footage. No 3d at all. (I think they picked what parts of the hand would be gold in Photoshop and then motion tracked that to the shot.)
You'll need to learn things like motion tracking if your camera is moving at all. Tracking and stabilization motion workflows in After Effects
You will also need to learn about rotoscoping so that things can go between the camera and the paint: After Effects Help | Rotoscoping
Storyboards will be very important so that you make sure you get the shots you need and so that everything flows well in post.
This is just some artwork overlaid and revealed with a simple wipe or mask:
if you did this in AE you would use the screen blend mode, animate a mask or use a wipe from the transition effects, then pre-compose the page and the artwork and apply a page turn effect to the pre-comp.
This is nothing more than an overlay with an animated mask:
In AE you would roto the hand to provide an edge matte for an image and the lens flair. The trick is the rotoscope and the blend modes. There may even be some displacement mapping going on. Again you would pre-compose the gold effect, set the blend mode to something like screen until you get the overlay you want, then use the roto as a mask to limit the effect to the hand.
All pretty basic compositing stuff. If you are new do some research and playing around with blend modes and look up animating masks and track mattes. Use the Search Help field in AE to find community resources for these techniques.
Thanks all for all the pro tips!
I will start playing with the colorama effect first, meanwhile a random question concerning Mr Mercury, is there a way to make Mr Mercury effect more realistic? Cus when i tried to play with it its kinda flat, white at the same time i found that i can adjust its rotation, as if its a 3d object. Is it possible to have it sliding / tripping off the hand?
Thanks so much!!!
Mr. Mercury is not very 3d, but you can get it looking pretty non-flat. Could we see an example of what you've got so far so we can make suggestions?
You can try using Particular. There are some good Particular fluid tutorials out there.