What is your current size?I think 1 inch in length and 0,5 in girth would be a good goal until february-may next year , if you're dedicated.More or less ofc.My advice would be set small goals , like let's say 0,5 by the next february,and when you measure next february if you only gained 0,5 you won't be deppresed or sad because that was your goal.And if you gain more than that you are going to be one happy motherfucker since you gained more than your goal..setting a goal of 1,5 inch in girth in 6 months it's WAY too big , i would say even 1 inch in 6 months it's some hardcore shit and i would be amazed to see that.I know every person it's diffrent but i feel like girth is harder to gain than length..so i would say hope for 5' in girth until the next february-may.That would be a 0,5 girth gain since you're 4,5 now.