Waiters/Waitresses and bartenders get tipped according to personality and service. Where I live, bartenders/waiters don't even make minimum wage and survive off of tips.

Food delivery gets about 1$ or 2$ tip.

Hair stylists get 10-15% on haircuts, depending on personality and how much I love the cut/experience I've had.

I've never thought of tipping a hotel maid, but then I never see them around when I stay at hotels and I tend to keep my room cleanly on my own. I have never really been around a doorman/porter, so I've no experience in giving tips in that instance.

Bag boys don't get tips, mostly because I tend to bag my own grocery's and also because I walk my own bags out to my car (where I live there seems to be a shortage of bag boys, the cashier or customers tend to have to bag things themselves).

I've only gotten one massage, and I do believe I tipped her because she was so friendly/kind and because I felt like butter afterwards. If person is friendly and I feel amazing I would tip in the future.

Taxi drivers get a tip, always. How much they get depends on how timely they are, as well as their attitudes. If the person is friendly, talks to us, makes jokes and such they're likely to get a much bigger tip than someone who is cussing and showing road rage and ignoring us as customers.