Hi Tina,
You can do this when you are collecting the find, or anytime afterward (you can also do this with items you liked but didn't collect yourself):
Just click on the small letter "i" in the left bottom corner of each item card. There you'll see a pink "banner" that says "Considering" with an arrow that points to the right. Click on that arrow to scroll through the different options (no need to save anything, when you close the card, the option you picked will be saved automatically).
I hope this helps,
Inge