Welcome to the forum mate. Did my test about 8 years ago so no idea on what advice to give. Theres a few peeps here who recently passed im sure they will be along soon to give you some tips!
did my theory test recently, best thing i found was the 2 free sample tests online. They're on the DSA website here.
you can register for free and you can take 2 mock tests (questions section only) online.