Guys;
The Female end ALWAYS goes to the side that will have Power, (Batteries, ESC). You don't want the live Male end to touch Metal accidentally.
For soldering the Deans plugs I recommend holding them in a vise or with Pliers held closed with a Rubber Band.
Keep both ends plugged together when soldering to avoid warping the connectors from the heat and always Pre-tin the Wires and Terminals.
I should add that the Power Pole connectors are a little easier to assemble, but are slightly larger in overall size when assembled than the Deans.