Herblore is a relatively important skill in Runescape, second to combat and summoning in my opinion. You can train high level Herblore to make some herbs for medicine which can cure you when you get damaged in fight or temporarily increase your abilities to win in the battle.
The slayer is one of the most skills of combat. You can gain some particular slaughter quests to gain more slayer xp. You can wear Runescape Slayer Masks to gain double slayer xp if you are members that pay for runescape accounts for sale monthly.
I highly recommend you wear runescape slayer masks! In addition, you could start your slaughter on Runescape to kill some high level monsters but you should make sure you are able to win the battle. Monsters are with some excellent drops and you can bury them for slayer xp.
If you want to find some useful guides to level high Herblore or Slayer, you can go to Farmer100 news or blog channel. Farmer100 is a professional website providing runesape accounts for sale for all RS gamers.