Resto shamans are amazing raid healers, with capacity to tank heal if no paladin are present in the raid, their totems bring great utility, and bloodlust/heroism. Usually since there are no enhancement or elemental shamans in the raid there is always at least one resto shaman per raid group.

Rotation for Restoration Shaman Wotlk

Healing Priorities

Raid heal: Chain Heal > Keep Earth Shield on the main Tank > Riptide on Use Lesser Healing Wave if a target is really low

Tank Heal: Keep Earth Shield on the main Tank > Riptide > Lesser Healing Wave for lower amounts of damage > Healing Wave for higher damage

Tips

Keep water shield up.

Save Bloodlust for the right moment, know the fight or wait for the raid leader to call for it.

Cast chain heal and riptide and take advantage of [Tidal Waves].

Use [Nature’s Swiftness] for an instant heal to save someone.

Use Mana tide totem to regenerate mana.