Use your Stimpacks to gain to experience just from one use. Then, find a very large group of like ten to twenty and fight extremely difficult units. This is also useful in determining if someone not on your friends list is logged on. You can use their first name or part of it. Note: The part of the command does not have to be their complete name. It will be yelled or shouted, and can be heard by more people in the chat window people that are farther away. Your text will appear as a thought bubble instead of speech bubble. If you have multiple skill, set the special moves of each separate profession on its own bar. You can drag it open so you have 24 boxes instead of one. The bar at the top is for your funciton keys.
When in that city, find another mission terminal, and repeat. You will end up with around credits from two deliveries that really are like one delivery. Then purchase a one way ticket to that city for around credits. Make sure both missions pay at least credits. Take two delivery missions at the same time that both will end up in the same city check destination coordinates.