Bad explained half of all steps missing.
Step 1 go to social and set your partylimit on how many players you want have in ur private lobby (set it on 2 ppl and after you did the glitch 1 other person can join the private room)
Step 2 find a pregame lobby and make sure its been enough ppl without you that the lobby starts without teambalancing issus
Step 3 wait until map is selected and when the countdown starts to start the map hit ps button and select any application that suspend your game (mediaplayer,youtube,twitch or spotify)
Step 4 wait around 1 min 20 sec (until the lobby with all the other ppl is fully started)
Step 5 hit ps button and switch back to bo3 (dont close the other application)
Step 6 now you should see that the timer of the lobby is freezed. Wait until it unfreeze and everybody should be lvl1
Step 7 the game launches. Wait until you can move and then invite ppl or tell them to join
Little sidenote
From a youtuber that want push his channel here i want see more research and a perfect tutorial. Its nice that you want help ppl but plz do it right or let it. You help nobody with a half tuto
Best gamemode that i found out for boosting is safeguard even for kills.
Round 1 2 and 3 dont secure the robot. Round 4 wait close to a end and secure it.
So u get around 15- 20 min time and getting around 5-6 kryptos and for fast wins secure it 1x and then wait 1 round
Just so you know, this isn't new dude. You might want to change the title of this thread. Go look at the upload date of this video and see for yourself: