Operation: Raging Arrow is a recruitment mission, and establishes the pattern for them. In the first part of the mission, your normal squad completes objectives that set the stage for the Agent's appearance, and in the second half that Agent has a solo mission, which ends with them joining your roster.
Once you've got your team back on the street, trigger this mission by walking any character to the nav point.
You'll get an objective to investigate a drop pod launcher. It's pretty hard to miss- the weird appartus under the dropship, next to the giant torus.
You'll face some helltroopers and swarm troopers here, but there's plenty of cover. Clear the grounds, of the first wave at least. Enemies will keep spawning, but you just need to a brief window to hack the machine at your nav point. If you can't clear them fast enough, try taking out the portable healing generators first.
Fortune is also quick to suggest you use her against enemies with shields, and it's not bad advice. Once you complete the hack, you'll get three targets on the machine. Shoot them all to destroy it, and complete your objective.
Loot the field and clear any remaining Legion who are annoying you. Don't forget to grab the crystal inside the torus.
There's also a crystal on the way to your next navpoint, hovering by the freeway.
Jump jump jump your way up to a hackable LEGION console. It'll summon a platform to the top level, but note that the spot underneath it is a prime spawn point for loot boxes. There won't always be one there, but odds are pretty good.
Now you can take the platform topside. Markers will show you destructable LEGION equipment- crates, cameras, power supplies and so forth.
You don't have to destroy everything marked- just enough to fill the meter at the top left of your screen. Troops will flood in to stop you, but no toughies. Just be careful not to let yourself get mobbed. If things do get thick, keep in mind that Hollywood's grenades work even at short range.
When the damage meter is filled, you'll get an objective to hack the antennae. Hacking it ends the mission, regardless of remaining enemies, so if you're quick, you can avoid tangling with the Blitztrooper Commander.
Either way, completing the hack ends the objective, and scores you your first outpost.
After, you'll get an earful from Friday, but wind up with an objective to secure a meet-up for Gremlin, marked on your map.
Hop on over, and knock on the designated door to get an objective for setting up disruptor pylons. These are pretty straightforward- go to the space and press 'E' to place the pylon. There are no ambushes, traps or wandering enemies to contend with.
There are, however, a ton of crystals at rooftop level here. Just looking around will yield at least half a dozen. If you're in the collecting mood, now's as good a time as any to scoop them up.
When you're ready, knock on that same door again to capture the meetup point, and complete the Special Investigation part of the operation.