Although this tip may seem vague, it is common amongst amateur filmmakers and photographers:
About 90% of the time what you see on the monitor is what you will see in the final results unless something is wrong with the camera or monitor screen. That is why it is important to adjust lighting etc. according to what the picture looks like on the monitor. If for any reason you feel it is going to look different from what the monitor is displaying; chances are you're wrong.