If you simply want to make a mule to get cash instead of building your character while doing it you have two options, either a Rescue mule or an Elusion mule.

Rescue mule: The easier of the two. Most people pick a certian kind of stats for their mule that help them build it as fast as possible. See those here. Now, quickly work your shal'ille spells to 25% in Raza since, well, it's free. =) After you leave Raza go to the Shal'ille temple and buy some spells. With the above stats you'll only need about 75% in your three highest spells to get level two. Same for level three. Viola. Once you have level three you have Rescue. Now, to get cash go to Cor Noth, the hall of geneology, and set your home town as Barloque. Run to Castle Victoria and pick up all the loot littering the ground. Sell Long Swords and Knights shields to Roq and your food, (25 edible mushrooms is 500 shillings) to Herbutte. Any reagents run to Tos and sell to Frisconar. You have to run by Tos anyway to get back to Castle Victoria. Repeat.

Elusion Mule: Basically the same princable. Use the same stats except now you have to go to the island to get your Riija Sword. Yes, you'll need help. =) After you get your Riija Sword and spells it's easiest to get reagents by looting kills in the Origin of the Kriipa or get a guildmate to help you. If you have a good main character they can get the reagents.

Once you've built your Riija mule to level 6 and have Elusion all you have to do is wait in Origin of the Kriipa and pick up all the armor and Nerudite swords you can. Reagents also fetch a good price with the exception of Rainbow fern. If you have any spare room fill up on Ivy Circlets (300+ a peice) and food. Elusion to South Barloque, run to Roq, sell, and Elusion back the the Aerie Guest house.

Enjoy!