Follow the instructions with the filter.
I disconnect the lines and then back wash them by opening the valve and letting some water flow into a large bucket, maybe 5" deep. This pulls some of the crud out that might be growing there, giving you a bit longer before you have to do a big cleaning of the lines themselves -- that is needed every 6 or 12 months.
Then, I put the canister on a large tray or kitchen counter and open it, remove the media and rinse in the bucket. Open it to clean the impellor well and remember to pull out that little triangle shaped thing in that narrow slot and clean under that with a tiny brush or pipe cleaner. Use a brush to clean the impellor itself and then reassemble. Use the lubricant provided, or silicone lube on o-ring and close it up. Hook up tubes and open all valves. Should fill with water and be ready to go when you are done with the water change that was going on while you tended the filter.
Member AGA, HAS, NASH
110G, 10 adult discus, barebottom with plants on wood
58G, 3 adult discus, barebottom with plants on wood
59G thickly planted tanks, rummey nose tetras, kuhlies
300G goldfish pond outside