This is guide is gonna be a plain and simple way to get 99 herblore
The costs should be between 100-200m
From 1-60 just mix the vial of water with marrentill without making any potions, seems slow but thats what ive found to be the fastest way to 60 for me.
Next once you reach 60 you can make weapon poison by mixing a vial of water with kwuarm and then adding blue dragon scale dust Do this untill you have 75 herblore.
The next part is making nulls, the best xp is here and makes the rest of the xp from 75-99 faster.
The first null is made by mixing irit and an enchanted vial until level 82.
At 82 the second null can be made by mixing kwuarm with an enchanted vial, this is done untill level 86 when the third null is made.
At 86 mix cadantine and an enchanted vial until level 99.
Although you can chose to make special restore potions (Energy potion (5) in game) to 99 instead but this is more expensive as each pot requires
an Avantoe and Enchanted vial.
Once you are 99 you can make a 4th null that gives a lot of experience with ranarr and an enchanted vial, if you want to get 200m xp or something.
Also these nulls do not affect the game although i would not recommend dropping and them but banking them or getting them all in your inventory and using ::empty.
Herblore Prices
____________________________________________
Vial of water 167 gp
Marrentill 374 gp
Blue Dragon Scale Dust 744 gp
Enchanted Vial 100k
Irit 50k
Kwuarm 60k
Cadantine 75k
Avantoe 300k
Ranarr 1m
Sorry for the lack of colors and pictures im not good with forums :S