Google Sheets beat Microsoft to the punch and introduced a Checkbox as one of the Data Validation options. You can go to Insert > Checkbox to quickly create one, and you can customize it by going to Data > Data Validation. I've updated most of the Google Sheets versions of my checklists to use that feature. I hope Excel gets smart and introduces a similar feature some day.
Don’t worry about making everything perfect at the outset. As the old saying goes, done is better than perfect, and the sooner you launch your membership site, the sooner you’ll find out if it’s what your target audience wants. It’s fine to return to this step later and work on making your membership website look more professional once you've got some traction.
If your eCommerce sells big brand names be sure to include their logo wherever possible. Having logos of big brands gives the customer an indication of what type of product you sell — plus, it adds some authenticity and prestige to your brand for being affiliated with industry leaders. Here’s an example of how Best Buy utilizes logos on their site:

In professional diving, checklists are used in the preparation of equipment for a dive, and to ensure that the diver and life support systems are fully prepared before they enter the water. To a lesser extent, checklists are used by a minority of recreational divers, and by a larger proportion of technical divers during pre-dive checks. Studies have shown checklists to be effective at reducing the number of errors and consequent incidents.

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