How often you need to check on your filter will vary drastically on usage. Obviously the more it’s used, the more contaminants it will be picking up, the more you’ll need to check it. A good general rule would be every 2 weeks. Most filters are white, so it’s easy to see if there is anything on your filter. If your hot tub filter is yellowed, or if you see bits of white build up within the pleats, it’s time for at least a rinse.
To rinse your hot tub filter, you can simply take your garden hose with a sprayer attachment and spray it from the top-down rotating it with your fingers as you go. Obviously in the winter that won’t do. You may need to bring it into the sink or tub to do a good job.