[Well, to start off, go to the shop keeper in yanille, and buy a bronze axe, and a tinderbox.
Teleport to Seers,MAKE SURE TO HAVE THE AXE EQUIPPED AND THE TINDERBOX WITH YOU. And start chopping trees - I have found it's easiest to light the logs as you chop, this way, you can keep cutting forever, never having to bank or anything. If not, just bank and light later.
(note: lighting the logs while chopping will not stop you from cutting, therefore, you will be getting woodcutting and firemaking xp at the same time.)
Tree Locations
Normal trees: Right outside Seers bank.
Oak trees: Beside the normal trees in Seers.
Willow trees: Behind Seers bank.
Yew trees: The church south-west of Seers bank.
Magic trees: Quite a ways south of Seers.
I only made this guide, because new players are not sure on where to cut trees, also to share the " Light while cutting " tip =D