First of all, being pale doesn't necessarily mean being white. It means having your skin in a one or two tones lighter than your normal colour. Many goths make the mistake of putting the Halloween white foundation on their skins but that only makes them look clownish, especially because many do the mistake of stopping at their chin instead of covering all the neck and ears too. :P
So..how to get a perfect skin for gothic style?
First of all, always clean your skin with cleanser specific for your kind of skin. For example, if you have greasy skin, go look for a mattyfing cleanser! Makes your skin opaque for all day and controls your face sweat. Use it to wash your face in the morning and at night. Right after cleansing, use a cotton pad and spray some tonic on it. You'll see it will clean your pores more deeply. Finally use a lotion to hydrate your skin (better if put before going to sleep!). Many lotions have a Sun Protection Factor (usually SPF 15) so it's good for the summer too if you don't want to get tanned.
After all these boring procedure that you have to too EVERYDAY, (don't worry you'll get used to it, especially after seeing the amazing results :) let's go to the make-up part.
1)Put a primer all over your face. This will make all the imperfections fade away a little bit (wrinkles, spots etc.) and will make your foundation last longer!
2) choose a foundation that's at least ONE tone lighter than your skin. I noticed that some foundations tend to get darker after put on. Try to choose a "cold" nuance if you want to achieve a paler skin. Please DO NOT choose PINK BASED FOUNDATION. That will make you look like a PIG! Choose a beige based one! It's even better if it is MINERAL based. Apply EVENLY on all your face. Eyelids too. (Use a brush or a little sponge of best results!)
3) let the foundation dry a bit (if it is liquid!) and then apply the concelear (this one too a tone lighter then your skin color!) on the imperfections that you can still see.
4) Use finishing powder to fix the foundation and make your skin opaque/porcelain looking :)
5) put the other make-up you need. Eyeliner, eyeshadow, lipstick etc and you're done! :)