The best co-op setting is an agreement.

Compare expectations

Ask whether the group wants exploration, a difficult challenge, a story chapter, or conversation with a game in the background. Those are all reasonable aims, but they do not always fit the same mode. Choose the session around the people who are actually present.

Make help welcome

Agree on how much advice is useful and let a newcomer try things before explaining every solution. Some players enjoy discovering a mechanic; others prefer a clear demonstration. Asking first turns help into a useful part of the evening instead of an interruption.

Choose the finishing point

Give the group a likely ending and make it easy for someone to leave without apologising. A short chapter, a few rounds, or one shared objective can make the evening feel complete. The strongest sign of a good session is that the group wants another one.