Hi, I'm a SSDC graduate with 12pts. I'm your senior now. Call me
korkor! 
Heh! Was joking ah! Don't take it to heart, seriously, pardon my
lame wits.
Okay shits aside, on
the serious note.
First you sign up as Private Student or School Student?
If Private, well, you can try going for their trial test, which
cost approx at most $8++ (if you book at home), $6++ (if book at
centre), before going for your actual BTT or FTT. I did my BTT as
private student.
If School, I didn't went for any lesson, at most I went for a
trial test for my FTT. I had convert myself from private to school
upon passing my BTT previously. Therefore I did my FTT as a school
student.
I'm not sure bout enroll straight as school student, cos I did
no evaulation test at all.
Hopes these helps. 
Perhaps other forumer can assist. Thank chiu bery vde muchy!

hey i same age as you lah. hahaha.
trial test is taken before the btt right? then must i do lesson
1 and 2 first then can take trial test or what? thanks!
and yes i signed up as school, not private! I tried calling them
for the past few days, but no answer at all man.