Upgrade your bags as quickly as possible - This tip is closely connected to the previous one. Upgrading your bags quickly will ensure that you spend more time grinding and less time managing your inventory, which will increase your leveling speed and allow you to make some more money in the process. Bags are expensive, so it is a good idea to look for a Tailor who will make you a set of new bags for Materials and a small fee (you will surely loot some Cloths, so this will not cost you too much). There are also some Quests that reward you with Bags:
Whelgar's Excavation Site - This Dwarven excavation site was overrun by Raptors (Mottled Scythemaws and Mottled Razormaws). These reptiles are a great source of Medium Leather (you should have Skinning Profession if you want to farm here, as a very large portion of income that comes from this spot is acquired by Skinning Raptors). They also drop some Vendor Trash Items and Raptor Eggs (these are convenient, as a Cooking Recipe for them comes from a Quest that is located just above the Site) that can be used for Leveling up Cooking Skill. However, the best part about this spot is that both Raptor types present here drop level 19 Twink Gear (Feet of the Lynx, Sentry Cloak, Redbeard Crest, and Twisted Chanter's Staff) that will achieve astronomical prices at the later stages of the Game (drop rates are very low, so some RNG is involved, sadly). Recommended Level - 25+.