For most western countries a visa is not required to travel to the Philippines, but please do check. You must, however, have an onwards ticket out of the Philippines. These are often not checked, but if entering the country on a budget airline they do usually check. On arrival you may stay 21 days. It is easy to extend your stay by either going to the local Immigration office (just over 3,000 peso plus 500 peso donation to speed things up), or easier, quicker and cheaper (just over 3,000 peso) simply overstay for up to a month and then pay as you leave the country (usually just prior to the airport immigration desk - they'll point you in the right direction). Also remember the 750 peso terminal fee when you leave the country!
Your tour largely depends on what activities you want to do: beach, sport, wildlife, adventure, city? In the Philippines it is best to move around every few days, unless you simply wish to have a beach holiday. After 2 to 3 days you have seen most of the sights in the majority of resorts, so moving around makes for a good holiday.
My favourite recommendation is as follow, but you should customise your tour to suit you:
Fly to Manila
Spend a few days in Manila - visit Corregidor and Tagatay
Fly to Taglibaran Airport on Bohol Island. Visit the Chocolate Hills, do the Loboc river cruise and go snorkeling.
Catch the ferry to Cebu and spent a couple of days in a luxury resort on Mactan Island.
Fly from Cebu to Busanga Airport in Palawan (maybe via Manila). Enjoy a few days here visiting Coron by boat, the Calauit safari park and do a little more snorkeling!
Return to Manila and spend a couple of days visiting the sights, museums and shopping for souvenirs and bargains.
Of course party time at Boracay or somewhere quieter like Camiguin may be on your list, so simply add or interchange, but remember to leave something for your next trip to the Philippines!