To get 99 range you will need to get your range to level 20 first to be able to use mithril arrows. Then you will need to get about 10k mithril arrows and start training. I suggest going to train at hobgoblins near melzars maze. Once you have 50 range you should go to the lesser demons and train from 50 to 99. Always remember to pick up your arrows because it is not economical to leave them to disappear.
These are a few tips on how to become a range pure: to become a range pure you must get your defense to about 40 or higher then get at least 90 range or higher this is a good thing because rune armor can only be penetrated by 90+ range (it doesn't mean that if you have range lower than 90 that you wont hit).
To get 99 woodcutting you need to get a rune axe first ,you can buy a rune axe for 15k about you should probably get your attack 40 to be able to wield rune items for more inventory space you will also need 41 woodcutting to be able to use a rune axe. You would probably think that cutting yew logs is more efficient but really willows are better. After that it's up to you on how much time you spend training this skill I have first experience on how hard it is to train a skill like this. It is very time consuming process.
I hope you enjoyed these tips ill be making more manuals at a later time