The only real tip for leveling a doc is to go where the wounded are. On Tatooine, I had a network of medic assistants in most cities, and when seriously wounded came in I took the shuttle over and helped them. Towards the end of my career enough docs had surfaced and I just concentrated on my own clinic in Moss Easley. When your PA or faction is involved in a siege, set up a triage tent with a ranger and treat the wounded there. And so on. The tips for getting warcraft gold through your massive crafting requirements are the same as with a medic: get a pile of organics and inorganic and go craft biological effect controllers or StimpackBs. As a doctor, you can donate, destroy, or sell the Stems you produce (with your training, they are very useful to field medics).
In a medium to large city, you will be the cornerstone of the medical effort. Any wound over 150 should be brought to your attention, and you will have to deal with everything if you are not fortunate enough to have an assistant. Get a crafting droid because you will almost never have time to run out to a private station. Eventually you will need access to crates of components; I recommend collecting all the doctors on a planet and distributing cost and access time. One factory can probably serve the component needs for five to ten doctors. You are essential to the health and well-being of your community, just as a doctor is in real life.