When I did mine I did it as part of a IT security group of certificates, I took about 6 months, but it was part time (evenings/weekends), and I did a few in that time frame.
Since curriculum overlaps a lot I figured I would take 4 certifications with little extra effort.
I studied for 2 1/2 months, took the CCNA-S and CEH exams, studied another 2 months and took the Security+ exam, then another month and I took the CISSP.
There is a huge overlap in materials and 4 certificates looks a lot better than 1 🙂
When I did mine I watched videos, read book, re-watched videos and took a full practice test (250 questions), then when I knew my weak areas I read the book (Shon Harris) and re-watched those videos, then another practice test and so on.
I would also visit a lot of forums, read on related topics and fill the holes I had in my knowledge (had a networking ITSec background).
Realize this is a management exam, think like management, not like a techie (that was my hardest challenge).
Realize it is a marathon not a sprint.
Take tons of practice tests, once you hit 80%+ consistently you are ready.