Regarding what to bring, you'll receive your enlistment notice
& there'll be one letter from SCDF advising you on what to
bring...as for your undergarments, bring a moderate number as
you'll need to change regularly to maintain proper hygiene...
Hair cut wise, its better to visit a malay barber & tell the
barber to cut no. 2 style otherwise during your enlistment, you
need to pay $3 if I'm not wrong & need to endure until around
6pm with all the hair on your body then you can bathe...hope my
answers are of help 