To up your slayer: go to a master and do assignments. Hopwever, do the quest first, that gives you access to a new slayer master, and so you can get slayer points. They are very usefull for making monet, or to get access to other stuff. You can do various slayer tasks with range, so you can level it that way as well. Overall, slayer is regarded the best way to level combat (and summoning). Quests to do: do the quest to unlock the summoning skill. After that, do all of the others. Which ones DID you complete?