You should directly solder the motor and esc wires together. For the battery you should use a deans connector. They are clearly marked plus/minus. It's much easier to solder something once and know the connections are right than to have to plug in bullet connectors every time.
Btw whatever battery you get is going to have bullet connectors that plug directly into the battery. You should put those bullets in the battery ONCE and leave them in. Every time you pull them out you risk damaging the battery.