To take an old item of clothing and to upgrade it. For example it is something like second handclothes from goodwill where the waist it too big so you see it to make it smaller.
I was up thrifting those old jeans you gave me! I just brought in the waist and painted them.
phrasal verb. throat up (to somebody) (informal, disapproving) to try to please somebody in authority by praising them too much, helping them, etc., in order to gain some advantage for yourself.