Prayer

Prayer is an unusual skill, as it is not increased by practising it.

For non-members, experience is gained in this skill by burying bones, while members have some extra options that can fast-track their progress.

The advantage of prayer is that it can give a temporary statistics boost, or other benefits, but the disadvantage is that it needs to be recharged at an altar or, for members, using a prayer potion. Once you reach level 31, you can use the Monastery altar which recharges to +2 above your level, making a prayer last slightly longer, though not granting access to any higher level prayers.

It also contributes toward your overall combat level, so do not raise your prayer level unless you intend to use it in combat.

Building experience
A simple way to build your level, pick up and bury every bone you see - the roadkill from other people's combat can be a free source.

Bones
While big bones are often stated to be great for prayer, it may be more effective to slaughter chickens and giant rats, if you can do it at least 3 times as fast.

Members can use Dragon Bones and other higher level bones, but have other ways to use them that are better than burying.

Prayers
One of each prayer type may be used together (defence, strength and attack), with the last 6 forming another group of which only one may be active. Using multiple prayers will drain your prayer faster, so pay particular attention to prayers that need to be active when you die (Protect Item, Retribution)

Clothing or Armour
please verify member/non-member items - the resources I'm using are unclear