The easiest way to pay for anything is by using cash in the local currency (some places will even accept US dollars in place of pesos). This means when you arrive in the Philippines you will want to exchange some money. If possible you should enter the country with a major currency, the preferred ones are the Euro, British pound or US dollar, these are easily exchanged. Be careful, when changing GBP there is often a different rate for Scottish pounds and English pounds, when in reality they are exactly the same. With the US$, you are guaranteed one of the best rates of all currencies.
Many hotels won’t exchange lesser currencies such as Thai Baht, this can be problematic if you are traveling within south east Asia. In Manila and other major cities there are lots of places to exchange money, and in Manila you get the best rates. On more remote islands the rate can be up to 20% worse than in the capital.
There are so many money changers in Manila that the competition is fierce and consequently you will get the best exchange. It is best to shop around to find the best rates, and remember the money changers give much better rates than the banks. When you have exchanged your money try to ask for smaller denominations as well as larger ones because taxis and bars won’t exchange large notes, especially outside the capital. Beware if you use a money changer rather than a bank or hotel, they are notorious at ripping off tourists so beware and always count your money.
NB: If someone approaches you in the street and offers to change your money into pesos at a great rate, DO NOT accept, they will trick you. Even if they count out the money in front of you with a clever sleight of hand you will lose some of the pesos. This is a time-old trick, especially in Manila, so be aware.