Level 1-20:
Follow the quest line till you gets level 10, it will help you get into the game fast and the quests at the beginning are pretty easy and there is marks to guide you to the right place. Don’t brother to get extra mobs since the experience of killing a mob is very little. And always take some healing potion with you. This will help you a great favor in critical condition.
Also you can queue for dungeons. But PvP is not a good choice for low level players since the gap between skills levels and gears will pull you down though your level will be lifted to 19 just look like others.
Against Single-target
The first caters single-target DPS and can be applied to boss fight or rushing down a specific target quickly. My combo chain here is:
Astral Seal（right-click) — Punishing Light — Searing Light — Sun Burst — Lance of Faith （left-click) — Guardian of Faith — Astral Seal
First debuff your target with Astral Seal and using Punishing Light until he touch you then cast Searing Light immediately. Use Sun Burst to get some hit points and damage the boss. The boss attacks in a very tardy movement. So you may use this fact and dodge the attack and distance the boss. This is the basic rotation. It is more complicate in real times, you should play by ear. Here is some tips:
Use Guardian of Faith as often as possible, this will not do great damage to the boss but also trip him which earns you more time.
Use Lance of Faith if you can’t cast punishing Light.
Use Healing Word when necessary.
-Against Multi-target
This one is handy to burn down a bunch of weak mobs speedily, which becomes Runescape Powerleveling really useful in adventuring zones and 5-player dungeons.
Astral Seal（right-click) — Punishing Light — Sun Burst — Searing Light or Lance of Faith (left-click) — Astral Seal — Lance of Faith (left-click) — Sun Burst – Flame Strike
Different from Boss fight, the mainly damage skill is Sun Burst which will commit scope of the damage and regain your hit points. Thus you should use Sun Burst once it is available. Flame Strike is better than Guardian of Faith when facing amount enemies. And you should move frequently to avoid great damage.
Source: 2p post