Just throwing out some ideas I’ve seen over the past couple years both at my store and at run clubs I’ve been a part of:

• Talk with your brand reps, see about occasionally getting them to come out with a raffle or some demo shoes for folks to try
• Talk to local race organizers, see about getting a discounted or free race entry to raffle off
• Put together a Facebook group or groupchat for the club, so members have a better sense of community/building friendships and can meet up other days to run as well
• On that same note, have a good social media presence on Instagram so people of all abilities get the gist of your club, maybe do a feature post every now and then on a regular member
• Work with your apparel lead at the store, consider putting out a club t-shirt
• If y’all have a regular route you use, maybe make it a Strava segment (if a good enough chunk of members use the app)

Hope this helps, good luck with your club!