Run a game night people can join without doing homework.
The hardest part is often getting everyone into the same place, with the same expectations.

Send one complete invitation
Include the date, time zone, game, platform, voice-chat location, and likely finish time. Say whether the game needs to be purchased and whether cross-play is available for the specific platforms involved. If there is a large download, remind people a day ahead. Do not ask guests to discover a required update at the scheduled start.
Decide what kind of night this is
A competitive session and a casual catch-up can both be fun. Mixing them without warning is frustrating. Put a plain line in the invitation: “Casual games, beginners welcome” or “Ranked matches; bring a regular team.” Agree on recording before someone starts a stream.
Make joining easier
Pin the current lobby instructions where everyone can find them. Let one person handle invites while another helps a newcomer with audio. If teams are uneven, rotate rather than leaving someone on the sidelines. For a larger group, a game with short rounds makes joining late less awkward.
Finish at a sensible point
Announce the last round before starting it. Thank people, post the next date if there is one, and avoid turning an optional evening into a recurring obligation. A group is easier to keep going when someone can miss a week without explaining themselves.