What can i do to my 35mm film to have cool lomo effects?

I've always wanted a lomo camera but i just recently found my dad's old nikon slr film camera. Is there any way to manipulate my film physically or my camera to have cool effects just like plastic cameras? Like storing it somewhere? Or heating it up? Also, how do i get the light leaks effect? I'd like to be able to create these pictures without using photoshop. Is that possible?

Short of jamming a pencil into the shutter as it opens, not much.