Pay-to-play Firemaking training

Firemaking is the easiest skill to train in F2P worlds, in both terms of casual training and power leveling. However, firemaking never makes profit enough for a living. This skill should be considered a competition skill in F2P worlds.

Training
Firemaking only requires some simple knowledge:
 * A tinderbox is needed to light any fire.
 * A method called power firemaking is possible to reduce firemaking time.
 * Ways of movement relative to firemaking, which can be seen here.
 * In order to make power firemaking successful, the tinderbox should be place at the center of inventory.

Level 1-14
Only logs can be lit, which yields 40 XP per logs. Trees, evergreens, dead and dying trees can be cut everywhere in Runescape, ranging from Lumbridge to wilderness. On second floor of Lumbridge castle, 4 logs spawn can be lit along with the logs brought by the player. Purchasing the logs is not nessesary as getting level 15 is only several minute's work, exactly 61 logs have to be burnt in order to raise firemaking from level 1 to 15.

Level 15-29
Oak logs can be lit, which yields 60 XP per logs. Oak trees can be cut almost everywhere. It is strongly recommended to have minimum of 15 woodcutting to cut the oak logs for burning, except for rich players who had left firemaking behind. About 183 oak logs have to be burnt in order to get from 15 firemaking to 30.

Level 30-99
Willow logs can be lit, which yields 90 XP per logs. Willow trees can be cut near the River Lum in Lumbridge, near Edgeville or... near the sea south of Draynor bank, or south of cabbage batch. They also appear in Rimmington. It is adviced to have minimum of 41 woodcutting and with a rune axe to cut willow trees, otherwise willow logs is always available at Grand Exchange for coins each. The power leveling cost is coins per XP. Willow logs, along with maple logs, are the main sources of power leveling in F2P world.

Level 55-99
Maple logs can be lit, which yields 135 XP per logs. Maple trees are not present in F2P worlds, thus the logs can only be bought from Grand Exchange for coins each. The power leveling cost is coins per XP. Willow logs, along with maple logs, are the main sources of power leveling in F2P world.

Level 70-99
Yew logs can be lit, which yields 202.5 XP per logs. Yew logs cut from yew trees should NOT be used for power leveling because the power leveling cost is coins per XP. Instead, yew logs should be sold at maximum price and bought at minimum price for power leveling.