Keep copies of everything you submit to Social Security.

Check out the "listings" for SSDI. They're broken down by issue by body system and mental health.

Tell Social Security about EVERY problem you have--not just the ones you think are important. For instance, if you have bladder problems, have a hammer toe, have MS, have anxiety/depression, have chronic bronchitis, and eczema--tell Social Security. Get all the records to back you up for that medical condition.

You can get your doctor to write a letter to SSA that discusses how your problem affects your ability to work. SSA won't care that your doc says he thinks you're disabled, that's SSA's determination to make in the process, but it will care what your doc says about how your problems affect your ability to do work related activity. And if your doc can include how often a month that you would need to miss work because of your medical/mental health problems, that would be good to include. Get friends/family/employers to write letters about the problems you have and how it affects your ability to do things related to work or around the house or with them. They can show before MS and after MS differences in your activity/ability level. If your employer was making any accommodations for you based on your problems, make sure your employer puts that into a letter--and for how long they were doing it.

Keep copies of EVERYTHING, including your medical records. Send in the names of the docs/facilities at which you were treated, the number of pages of medical records, and the dates the records covered (for each medical provider) to Social Security with a letter indicating the records are enclosed.

And if you're denied, appeal the decision promptly. All you have to say is, "I disagree with the decision. I believe I am disabled." as your reason to appeal. (note that isn't a long song and dance explanation and is pretty vague) Don't give up if you think you're disabled. And then seek the advice of an attorney--preferably an attorney who does SSDI/SSI work a lot--like a NOSSCR (google it) attorney.

Here's another post I made about this stuff. Sort of similar to what I've told you, but there's additional stuff in there. http://neurotalk.psychcentral.com/post195950-6.html

Good luck and feel free to PM me if you have more questions.