1. Task
There is a small camp guarded by Sha'tar to the southwest of Auchindoun in Terokkar Forest, with a few quests. There are also individual quests in places like Netherstorm and Shadowmoon Valley that will increase your reputation.
2. Brush a copy
The easiest way for players (and the only way except for limited missions) is to farm three 5-player dungeons in the Storm Fortress in Netherstorm: Ecological Ship, Energy Ship and Forbidden Prison. The team's deputy Storm Fortress does not provide reputation, but before starting to earn reputation, it is best to obtain the emerald green magic orb (green sphere) dropped by Kael'thas. After giving it to Adal in Shattrath City, everyone in the city will receive the Buff "Adal's War Hymn". The reputation in the above three dungeons is increased by 10%, which can be stacked with other reputation bonuses. This buff lasts for 2 hours and is only consumed while you are in the three instances mentioned above.
The following is the situation when each dungeon is completely cleared, excluding any reputation buffs:
Eco-Boat (Botanica, entrance at 71.7, 55.0)
Normal mode: 2200 points (120 points for boss, 12 points for mobs)
Heroic mode: 3320 points (250 points for boss, 15 points for mobs)
Energy Ship (McNair, entrance at 70.5, 69.6)
Normal mode: 1633 points (120 points for boss, 90 points for mini-boss, 24 points for destroyer, 6 points for imp, 12 points for other mobs)
Heroic mode: 2621 points (250 points for bosses and mini-bosses, 30 points for destroyers, 8 points for imps, 15 points for other mobs) Forbidden Prison (Actriz, entrance at 74.4, 57.7)
Normal mode: 1657 points (last boss 240 points, other bosses 120 points, humanoid mobs 12 points, demon mobs 24 points)
Heroic mode: 2540 points (500 points for the last boss, 250 points for other bosses, 15 points for humanoid mobs, 30 points for demon mobs)
The above is the relevant content about how to increase the reputation of Sha'tar in World of Warcraft. I hope it will be helpful to you!