With bones and muscles, memorizing them is pretty much the way to learn them.
Anyone that has read any of my anatomy posts will know that I swear by taking pictures of everything. (Ask permission first.) If you aren't able to take pics, look at the Anatomy thread in the stickies and visit those sites. (I have pics of bones, but no quizzes for them, but I do have quizzes for the muscles.)
You pretty much have to point at a body part, name it, then point at the fossa, etc that you need to know on that bone, and name it. Do this for each bone, or muscle, etc.
Go over and over, in your mind, or really pointing if at home.
As for the skull, yes there are many little "holes and crevices" to learn. :chuckle
I took a picture, printed it out twice, labeled one, but not the other. I studied from the photos. (I also have a little skeleton I bought on Ebay that I studied from as well.)
Pics are AWESOME! They will serve as your lab when you are not at school. There are plenty of pics online, if you aren't able to take pics in your lab. (Remember, your instructor may pull out models that you've never seen before as well. Therefore, seeing and learning from a variety of models will be an asset.
Learning the processes, etc on the inside of the skull is necessary as you will find them helpful when learning the nerves, etc. that run through them.
Don't get discouraged!!! You can do it!!!