I've recently begun doing a lot of editing, and I'm having problems keeping the levels of the different parts consistent. Were talking usually about 20 minutes of video for which I do all the sound design and editing. Any tips for keeping the levels consistent? Are there any tools or tricks for this? I'm pretty inexperienced, so don't hesitate to mention all the otherwise obvious tips.
If you're inexperienced, one beginners trap is not using a consistent monitoring level. Ideally you should line up your monitors to a set standard, but most important of all is making sure you put a mark on your master level control (on the mixing desk faders or whatever is feeding your monitors) so that when you edit you are always listening at the same level....
(ignore this if you already are aware, but if not...)
I think you're talking about the mixing process. This is a very wide ranging topic for which there are no 'quick fix' tools or tricks. A decent starting point may be to find an area in your video that you feel best represents the overall tone and content and work on that for a while. Make sure you're getting the dialog (or narration, or whatever is supposed to be telling the story) loud enough so you can understand it but not too loud as to overwhelm everything else. It should be playing back at a comfortable level. Once you've established that sequence and feel that it's in good shape, use it as the reference point for the rest of your video.
There is SO SO SO much more to say and learn about mixing. Proper mixing involves metering, correctly calibrated speakers, monitoring systems, etc. I hesitate to even tell you what I've told you already since a little information can be enough to do some damage. Let's see what the rest of the SSD universe has to say on the matter -
Use your ears and your level meters. Surround scope, phase scope, hardware or console, third party plugin... Most of the time FX and music levels will have to make room for dialogue so concentrate on getting dialogue levels consistent then use your ears to level the other elements in relation to the dialogue. Keep in mind that levels and consistency will be focused on during the mix.