Which one to learn first: Special or general relativity? I am extremely interested in self-learning Einstein's theory of relativity, but I don't know where to start. 
Can I make general relativity my starting point, and later look at special relativity as a special case of GR? Is is doable for a person with average math skills?
 A: Before learning general relativity you need to learn special relativity,classical mechanics,electromagnetism,fluid mechanics,tensors,differential geometry first.
this is the way we physics majors learn general relativity.
We learn ofcourse quantum mechanics,statistical mechanics,optics too,but these are not directly necessary as far as I know ,but to understand general relativity you need to have lots of experience of doing physics.
For self study  you should watch Leonard Susskind lectures first.
A: Can I make GR my starting point, and look at SR later as a special case of GR?
This would be like making differential geometry your starting point and then learning linear algebra as a special case --- or learning calculus as your starting point and then learning about straight lines as a special case. In other words, it's insane.
A: Edwin F. Taylor and John Archibald Wheeler,
Spacetime Physics: Introduction to Special Relativity, 2nd ed.
W. H. Freeman & Company, 1992.
In print, ISBN 0-7167-2326-3, list price $26.00 (hardcover)
Simply the best introduction you could get.  You want to start with SR.  Make sure you have a good grounding in Classical "Newtownian" Physics first, as well as some good higher level math classes.
A: Believe me, if you haven't studied either yet, special relativity will be enough to blow your mind. Learning it will keep your curiosity peaked and hopefully lead you to learning new math and more physics to the point where one day you are ready to study general relativity.
