by request! 
ok.. there r obviously 2 scenarios for taking MCs - outside camp
and inside camp.
in camp: usually means after the first parade, there will be a sick
parade, where all the report sick ppl will fill in the report sick
bk and forms, the duty sergeant will get the time to report sick
from med ctr. at the given time he will bring all the sick birds to
the med ctr. the outcomes are quite well known:
att a: nothing wrong wif u! better start to think of some excuse
for y u report sick! 
att b: light duties: senang lor.
att c: theres no more att c bunk - only att c home. pack ur bags
and get ready to fly!
excuse xxx: u may be fit to do normal things but excuse watever
activities tt involve xxx. the most common xxx are upper limb,
lower limb, footwear... the more bizarre ones are sunlight
, grass,
uniform...
in cases where the illness / injury is more severe they may make
appointments for u to go out to c specialist / go cmpb for xray,
etc.
out of camp: say u book out and see doctor. various camps would haf
different policies, but they will not differ much: u may either be
allowed to stay home (if u r given att c by the doctor) and come
back when u r ok, or in some cases u haf to bk in as per normal.
the common process is that of bringing the mc for endorsement, esp
when the mc involves att c for more than 3 days or excuse this and
that or anything serious. for the case where u haf to bk in as per
normal, usually they will let u report sick the nex morning to
endorse mc and bk out if given endorsement. if not u will still
need to endorse ur mc after u come back frm u att c.
hm.. hope i haf covered the basics and most common scenarios!