How to let go of excess weight?

For a while I've struggled with the fluctuation of my weight. Years ago I weighed about 251 and within less than three months I loss 80 lbs. I will admit in the beginning I didn't handle the diet properly. I exercised to the extreme burning a lot of calories, and I was eating but my portions we weren't big enough. Then after while when I started getting on the right track I began to slowly quit my exercise regimen. After while I did attempt to start back by going to Curves and eventually let go of Curves that was back in 2006. So for the next few years I deal with the fluctuation of the weight because for the longest I was reluctant to exercise. After while on a doctor visit I asked for my blood sugar levels to be checked and it came to be I was borderline diabetic. Afterwhile I was able to push my self to exercise but now my main concern is my problem areas the excess tummy from the weight loss, and my arms. I just want to know how to get rid of excess tummy and and tone the arms up inexpensively and correctly.