Order of the Cloud Serpent

This Faction got their base at The Aboretum in The Jade Forest.
Only level 90 players will be able to start this grind. Once level 90, an npc at The Aboretum will offer you the first quest.

You will have to complete a questline in order to unlock the daily quests.

The dailies involves both professions (Fishing, Archaeology, Cooking and First aid) and kill/gather quests. The profession quests won't grand you more than around 130 rep each quest. The Kill and gather quests will award 500-650 rep.

Like farming the netherwing reputation, you will be able to collect eggs which can be turned in as additional reputation. They are huge and grey called Onyx Egg and are to be found all over Windward Isle. With these you can really speed up your grind, if you are going for a serious and fast rep grind.

Our friend who sells Jewelcrafting Designs and the serpent mounts is San Redscale

Depending on your current reputation you will be able to purchase:

Note - Once you reach exalted, you will recieve one of the cloud serpents for free along with the permission to ride serpents. I got the Azure one, not sure if it's random or anyone can confirm this?

Honored:
Design: Jade Panther
Design Sunstone Panther

Revered:
Design: Ruby Panther
Design: Sapphire Panther

Exalted:
Design: Jeweled Onyx Panther
Reins of the Golden Cloud Serpent
Reins of the Azure Cloud Serpent
Reins of the Jade Cloud Serpent

Good grinding!

As 5.0.5 this achievement can be given cross characters on the same WoW account only, characters you have on the other WoW account but on the same Battle.net account will net get the achievement. Sadly.