My basic advice for establishing a good picture would be as follows:
Don't have contrast too high in relation to brightness. If contrast is over 90 and brightness under 50 the picture may appear too stark and result in loss of detail in dark and bright scenes. In such a case try to find a more agreeable balance by lowering the contrast and upping the brightness until you get an image more to your liking. As a general rule of thumb you should be able to make out detail in dark/bright scenes such as ruffles on a piece of black or white clothing for example.
I would also turn off any additional colour processing options that usually have names like 'live colour, vivid colour etc' and just adjust the basic colour bar to your preference. As close to how colours appear in real life is a good barometer, ie as natural as possible.
One final aspect that I personally consider important for fast moving images such as sports is motion processing which can usually be set to off, low, medium or high. If your screen exhibits judder during panning shots or with fast moving objects then increasing motion processing will likely eliminate it. It can however, at higher settings, appear overly smooth and unnatural which can be uncomfortable on the eye.
Those are the important basics that I'd recommend tinkering with in order to establish the bedrock of your picture.