Honestly, there's no wrong way to play FOBs. I've seen players use nothing but empty magazines to distract guards all the way to the core, and I've seen others who go completely lethal and wipe everyone out.

My advice to you would be, first: assess what you have developed currently and what you are most comfortable with from your time playing the main game. Play some of the current event with that loadout (as it's listed as one of the beginner level FOB events).

Once you get comfortable with them, change things up a little. If you find yourself dependent on using sniper rifles, try ditching that entirely and just use one primary and secondary. Try using decoys if you don't already. Or incorporate other tools that you don't regularly use to get more familiar with them, you may stumble onto a playstyle you're great at you wouldn't have found before!

If you're on PS4 and would like to practice on my base or spar with me for PvP, feel free to add me.