In addition to writing I also line edit. Recently I was given a manuscript to line edit. Within the first chapter I found several factual errors. Things that a modicum of research could have corrected. So I decided to post another blog on doing your "homework".
Remember you never know what your readers experiences are.
1. If you have a character who is a doctor and he/she makes a diagnosis - you better have researched that disease until you know every symptom, what the usual presentation of it is and what could be a really unusual presentation. You need to know the test that are used to diagnose it, the treatment for it and if you can find someone that has a loved one with or has the disease. Nothing better than first hand knowledge.
2. If you are writing a soldier with TBI or PTSD make sure you know the differences, the treatment, the prognosis, the VA disability rating percentages and the pension they recieve for it. Talk to a soldier, or your local VA office or VA psychologist.
3. If writing an artist - learn about the field. What are the different techniques, the different disciplines, the different materials. Take a drawing class or go to your local college and talk to an art professor.
4. If you are writing a student - go by your local college's registration office and ask for a bulletin that will have the requirements for every major they offer. It will also give you the summary of each class. If you decide that you need a scene where the character is in class find out when it's offered and approach the professor about sitting in on a class one session.
5. Writing a police officer? Talk to one. Pick up the "Howdunit" series.
6. Writing something where a character uses a sword? Go visit stores that sell them. Feel the weight or if you can afford it buy one then hold it for five minutes. Feel the burn it puts on the back of your arm, your wrist.
7. If you write science fiction make it believable.