I usually have two loadouts;
Stock
then:
Frontier Justice,
Wrangler/Pistol
Gunslinger
Stock is generally the best go-to if you're planning to turtle and camp, whilst the Gunslinger combo's for getting around, usually for offense.
Defensive strats:
- Always build a dispenser first, near a bunch of teammates, yet in a safe position so you not only benefit everyone, but get some more protection for your buildings.
-It's usually a stuff idea to stay way behind with your buildings. Closer is better as you can aid more.
Offensive strats:
The best option is to build a minisentry behind a corner, and lure people around whilst mass-firing the FJ or a pistol, and if you evade well enough you'll easily pick them off. And if someone gets rid of it, you still got dem' crits.
Don't forget that even on offense, teleporters and dispensers are still really useful
and thats my mr. captain-obvious mlg mtn dew + dorito supported guide on my engineer playing skills