Tipping is generally similar to how you would tip in the U.S or Canada. percentage wise, 10% to 15% is generally an acceptable amount on the bill.
Easiest way for a tourist to remember is to tip a maximum 15 pesos for every 100 pesos you spend on a meal with good service, If you feel you were short changed and given poor customer service, then 10 pesos on every 100 spent.
If your tipping in US dollars, then just remember the average exchange rate is around 18 pesos to the $ 1 US dollar. Tipping a U.S dollar for every 100 pesos is generous and more than acceptable.
For other situations:
Tipping Hotel / Bar Bartender - Could be 10 to 20% of the total drink bill. ( $ 1 dollar on every 100 pesos spent or 20 pesos on every hundred spent is generous ) and easier than trying to work out percentages ! Delivery Person - Could be tipped between 20 to 50 pesos or $ 2 to $ 3 US dollars minimum.
Restaurants/ Bars/Clubs - Tipping is generally 15-20% of the bill ( $ 1 U.S dollar on every 100 pesos spent or 20 pesos on every 100 pesos spent )
Baggage Handling - 20 to 50 Pesos (about $1 to $ 4 USD/CAD). A bus driver could be tipped $10 to $20 Pesos if luggage is handled ( $ 1 to 2 U.S dollars ) a chauffeur, between 50 to a 100 pesos ( $ 3 to $ 5 U.S dollars ) a porter could be tipped 50 pesos.
Housekeeping - Could be tipped around 20 to $50 Pesos per night but if you want to make sure it's the housekeeper you liked that gets the tip and not the one that just came in on your last day who ends up with all tip, avoid a lump sums at the end of your stay.
Parking Valet - Can be tipped 20 Pesos, though some may suggest up to $50 Pesos.
Room Service - can be tipped 20 Pesos, though some may suggest up to 50 Pesos. ( $ 2 to $3 U.S )
Transportation/ Taxi – If they assist unloading baggage or do something extra like make a few stops along the way a tip is always appreciated, 20 to 50 Pesos minimum. ( $2 to $3 U.S ) , Some routes have a standard flat fee to or from the airport.
Bus Tour - It is customary to tip both the host and the driver so 50 pesos each is sufficient or ( 3 U.S dollars each ) unless you are a generous tipper, then $ 5 U.S dollars is a great tip for each one .
Grocery Store – Baggers appreciate tips, it's suggested 10 to 20 pesos ( 50 cents to a dollar ). The baggers are often school children or the elderly and they do not make wages, only tips.
Gas Station Attendant – 10 to 20 pesos per fill up or 1 US dollar.
Hair Stylist / Barber - could be tipped 50 to 100 pesos or 3 to 5 U.S dollars -
Spa Service - massage therapist could be tipped $50 to $100 Pesos ( $ 3 to $ 5 U.S )
Note : To keep it simple , tip what you feel is fair but don't be cheap, the service industry relies on tips. Paying the bill and adding the tip on the bill is usually split between employees and on occasions it is Known for a bad boss to keep the tips. If possible try and leave the tips in cash.