Cartography
Cartography is an essential skill for those who wish to go treasure hunting. You require a Mapmaker's Pen in order to craft maps of your own. You may only draw maps in the facets of Trammel and Felucca. Trying to draw maps elsewhere results in an indecipherable Map. NPC Mapmaker Vendors will sell you standard maps to draw on but you can also overwrite the pre-drawn copies they sell. Blank Scrolls can also be used to create maps. Note that while Cartography is required to initially decode Treasure Maps (done by double clicking them, this removes the term "tattered" from their title), once this is done any character can read them as long as they have the minimum required Cartography skill.
Take gold to a Mapmaker, buy blank maps and pens, and sell your completed work as you go. With luck you won't have to return to the bank for more funds.
Training:
0-30: - Buy from NPC Mapmaker
30-50: - Local Maps
50-65: - City Maps
65-99,5: - World Maps
99,5-100: - Level 3 and 4 Treasure Maps (adeptly & cleverly)