Building a good list of subreddits to check is very important. This list should include subreddits that are relevant to your niche. If you provide a bad list, you will get bad results.
Please avoid super popular subreddits (example) because they all have active moderators!
There are a few easy ways to create a list:
Type in your niche related subreddit and get a cloud of suggested subreddits, that are similar to the one you typed in. Press ctrl+a and copy, then paste when you order. You should get a list of subreddits, each in its own line – exactly how it needs to be done.
Similar tool, type in your subreddit and get suggestions. Copy the subreddits and paste when you’re finishing the order. Format is perfect and suggestions are good.
Example of a list that you have to send: