1.Go to polarr and then go to your custom filters scroll till you find import filter. Three options will come up if you want to scan a filter from another device click scan filter and scan your code. To find more click filters click filters by polarrists. To import from your camera roll  click important from photos. Find your filter and upload it.

2.Scroll to find your new filter and add it to your photo save when finished.

Here are filters I made:

Chris looking cute as heck XP hope this helps! Happy editing lovelies!