4. Effects Order

Usually you'll want a gate before any other effects. It really depends on how you're using it and what other effects you're using. If you're just cutting space between drum hits, for example, you would want it first. If you had distortion on the drums, you may or may not want the gate after the distortion. (Before distortion would give you distortion crackle after hits, after distortion would remove that.) This is all ultimately case-by-case stuff.

After the gate (if you're using one), a compressor is typically next in line. If you put a compressor before a gate, it would narrow the dynamic range and make it more difficult to tune the threshold of the gate. I usually put the EQ after the compressor if I'm using both. If you put the EQ before the compressor, and boosted the highs, for example, they would be pushed further over the threshold and compress more. You can use this reversed order to your advantage if one frequency range is too dynamic for some reason. Usually its easier to use a multi-band compressor.

Sometimes if I'm using delay with a really high feedback, I'll put a compressor at the end of the chain to combat the volume boost from all the repeats compounding on each other.

Putting a compressor on your master output can sound really cool and help boost the volume a little bit. This is another case where I'll find myself putting and EQ before a compressor sometimes. Master output effects are best saved for last. If your mixing with a compressor on the output you may get a false reading of how loud certain tracks are. However, on the final mix, compression can help to boost volume and smooth everything out. You don't want to overdo compression here. Typically a low ratio (1.5:1 to 3:1) is good. Really short attack and hold, short to medium release. Back the threshold down enough to get 1dB to 2dB of gain reduction, then add it back with the output gain.