Starting off at some mid level? Come into the guide from any level, scroll through, find and click the level you want to start with, and the guide will take it from there. Zygor suggests starting the guide a level or two before your level. This is to allow you to work you way into the local quest chains. Just skip the chains for quests you didn’t pick up along the way, or the quests that you already did.
DoTs: Assuming that the mob is going to live for certain periods of time, it is worth it to place DoTs up. If the mob lives for at least five seconds, cast Pain. If it lives at least seven seconds, cast VT. The ideal time to cast DoTs is when it would be replacing Flay, but you can substitute Blast if the mob will live longer. Make sure to cast Bolt on cd though!