You can do it online through htt://www. usps. com or at your local post office. Package the item, fill out a customs form, and you will be charged by the weight. It's not hard.
There are different online websites which helps to send the goods to them. There are auditing and many consulting services that provides such kinds of help to send something to a friend in Ukraine.
Hey, i'm Ukrainian actually. AFAIK, you need to go to the post office, and send your goods as donation. Otherwise your friend may have problems with custom. Good luck