FT's can be very difficult to navigate, especially with aggressive opponents. Stacks are generally very short, which means a lot of shoving and ICM is a major factor.
I would recommend studying ICM, there are plenty of books and online content out there.
Also, Gareth James has just released a new book called The Final Table. I have not read it, so I can't comment on the book specifically, but Gareth is a great teacher, so I'm sure it's worth every penny!