Maybe send down a landing party or two and hang out with humans for a bit incognito. Knowing about us isn't the same as interacting with us. At least that's what I think.

As for actual communication, it's a tough question. My first contact education is based on TV and movies. Hopefully they have a procedure based on actual previous first contact experiences.

Probably crop fields because its funny

Buy all our world leaders and make them say stupid shit and shoot things at each other for a few centuries. Then replace them all with some social website and gradually announce their presence and act like saviors.

We're ready now, please come!!

They would simulate us in a high fidelity simulation indistinguishable from reality [1] in order to test how to interact.

[1] Like the one perhaps you're in right now.