I'd appreciate experienced dippers' advice...
Make sure your basecoats are very bright, since the dip darkens everything. A white primer is usually better than black for this.
About a minute after you slather it on, wick some of the dip off with an old brush, leaving just enough for it to settle in the crevices of the model.
If you want to pretty it up later, wait until the dip is completely dry (at least 24 hrs), hit it with a light spray of matte varnish, and then go back and do some simple highlighting using the original base colours. (The matte varnish will give the highlight paint a surface to grip onto.)
Use brown tone dip for models that are primarily brown, red, yellow, orange, gold, etc: warm colours. Use a black dip for models that are primarily blue, silver, green: cool colours (the brown dip just makes them look drab or filthy).
Happy dipping!