Burn maple logs once you are able to....then keep doing that to 99. This is the cheapest way to get 99 FM if you feel like spending alot of money then use higher ranked logs.
Probably something like 100-150 hours.
It takes approximately 1.5m willow logs to get 99 FM starting from 30 firemaking...i recommend doing willows until 50 FM, then buy about 100k maples...and u should be about set =P
96,551. :) good luck
Mine is 60 though I'm trying to get it to 99 but I'll probably be 100 by then lol I'll umm update this if i get it to 99!! Mine is 87 >.< I'm also working on getting 99 too, but it is getting kinda boring lols mines 53 >.< though im gettin 99 in it and FM, my FM lvl is 80...close...<.>
You will need 150k willow logs to get 99 firemaking. I suggest using maples and yews after because it is faster.
You would be looking at around 2 - 10 weeks, but this entirely depends on how long you will be on runescape training the skill a-day.
The total exp is 13,034,431 experience for a 99 stat on RuneScape.
There is a girl that has 99 on all skills her runescape name is 'xxphatmagexx'.
TRAIN
you train it
There are no cheats in RUneScape. Getting level 99 in ANYTHING requires a considerable effort.
you keep training your skill to get up to lvl 99