Apparel is an important part of any gym. It helps to add a sense of community and can also be great advertising for your business. You should look to produce T-shirts, singlets, tanks and hoodies, which are the foundations of any gym clothing store.
Ensuring that your logo and branding is consistent across all clothing is extremely important so there is no confusion and enables you to project a professional image within your gym, as well as into the local and also your wider niche community. Creating and designing apparel for the gym should be done before the business opens, ideally. You don’t necessarily have to order it to be printed immediately (especially if you’re on a tight budget), but it will save you time and potential stress once you’ve opened.
Something to consider would be the amount of apparel you order. Some businesses order in bulk, but it can also be wasted money that could be directed elsewhere (in items that mightn’t get sold for several months). Setting up an online shop in conjunction with your gym’s website is an efficient way to go. Order a small amount of each product for members to see what the apparel looks like off-screen, and also for potential on the spot orders. Alternatively, buy a small amount of each product & its respective sizes, and then take small group orders on a semi - regular basis. Another option although not as desirable, would be to keep a list of what has been sold, and then simply replenish stock as it is needed.
Pricing apparel can be difficult, as high-quality items are obviously more expensive. Keep in mind that if you provide your clients with items of superior make, they will notice this and appreciate your care (not to mention they will last longer!). If done right members will be more inclined to wear your apparel outside of gym training days and to social gatherings.
Apparel shouldn’t be relied on as a major source of direct income, as sales can be few and far between, and actual money made per shirt will likely not be very much. However, having something that visually brings your members together as a team, and exposes your business in the wider community is definitely worth it.