Complete a Co-op mission.

In order to get this achievement you must Complete a Co-op mission.

1. Co-op missions will unlock in sequence 3 so you can't get this achievement until then.
2. Once you unlock these missions they will appear on your map as a Brown/Orange icon either with a thieves mask for a heist or two people for a mission, either one will do.
3. Go over and start the mission, once the mission/heist is done you will get your achievement.

Make sure you have got these missions unlocked before you attempt to do this, this will make it easier for yourself and save some grief.
These missions also give you decent amount of IG money so it is in your interest to try it.
This can be done alone you do not need a friend to do this with.

If you need any help feel free to PM me.