Backyard bbq Wedding

You can create signs saying, "cocktail hour this way!" or "this way to the food!" or whatever works best for the tone of your wedding.

Also, if there are buildings use said signs and the officiant to make it clear which ones are for your guests, and which ones are not.

People generally follow the crowd at weddings. They know not to get in front of the camera for portraits when the photographer is filming unless they are invited to do so. Typically people use that time to serve appetizers and drinks while guests mingle. Formal wording isn't needed or used. People will figure it out on their own so I wouldn't worry.

I totally agree Jana! People follow the crowd!

You can have some signs directing your guests, add a note in your program, and have your officiant tell your guests where to go next before the recessional!