Whow can I avoid moths in The closet?...

Do you own a lot of wool? If you do, it is suggested that you carefully love over everything, make sure it is clean and then store the clothes in airtight containers or zipper bags. Also, you don't have to use moth balls but cedar chips or cedar lining helps to deter them. You should be diligent about checking wool clothing at least 2 times a year and vacuum out the closet regularly.

Use cedar closet blocks and make sure there are no holes per say that they are coming in.

Put a few moth balls in a piece of cheese cloth or plastic bag with holes in it in the corner of your closet.

I have my few wool items in ziplock bags with sprigs of dried lavender. And cedar blocks in the closet for good measure. I have picked them up cheaply enough here and there from Ross, Home Goods, etc.

Walmart has some cheap cedar thingy's that you put on the hanger (looks like a flat donut). Works great and was less than $5 for 4.

I use what Mattie is describing however I purchase the hanging cedar strips from Amazon. Moth balls can smell up your clothes and cedar can repel more than just moths. Depending on the abundance of items, removing the stuff from the closet, cleaning the walls or freshly painting it, then adding the cedar should help your issue. Good luck!