I wouldn't bother with speaking Singlish though. Personally I think foreigners speaking Singlish come across as embarrassingly desperate and pathetic (nothing more so than white people who refer to themselves as 'ang mohs'). They may laugh for a few seconds, but they'll respect you less for it. Be yourself.
I agree speaking Singlish can sound ridiculous even if you can use lah , loh , leh , hor, mah etc etc correctly , however as I am surrounded by local folks in my office I have unconsciously adopted the use of "anyhow , can , cannot" and shortening my sentences to only the necessary words as that's how my daily work chat goes.
As for using ang moh , I always use angmoh as I would never use Caucasian as its never been in my vocab and sounds weird, so I may as well go with the local description of whitey.