A rabbit ear fold is a specific origami fold in which one corner of a square of paper is folding in half to produce a sharper point. Detailed instructions for folding a double or single rabbit ear can be found at: http://www.anyone-can-origami.com/basic-origami-2.html#basicform8
"Ori" means fold. Like in "origami". In origami, ori is fold and gami is paper. But it gets complicated because when "gami" is not in a compound work it is "kami". So paper is "kami" when not in a compound word.
There are a number of online sites where one can get directions on how to make an origami star. Basically, there are 19 steps involved and these are outlined and demonstrated at Origami Instruction as well as on several YouTube videos.
An inside reverse fold is a very common fold used in origami. It is very easy but requires practice. You must open your artwork, fold the piece in then re-fold it together. Or you can simply push the designated are of the piece "into" itself.