First thing to do is just change the type of carbs you eat. Instead of eating simple carbs ( chips, donuts, candies etc) eat some complex carbs ( sweet potatoes, rice, oatmeal etc) that will make a huge difference within itself.
If you dont see any changes doing this (most likely you will) then u can think about cutting your carbs, and I wouldnt go as drastically as cutting to 100 g a day, that is just too big of a drop. Just cutting out 20g a week (350 grams per day, instead of 370g per day) would be easier for ur body to handle, and u wont plateau as quickly that way, as you would just shutting down and dropping to 100 grams a day total.
This is just a start, if u have any more questions, just PM me.