I will keep this short and simple, since it's really not necessary to go too much in detail.
If you love Wood Cutting then this shoud be your Major souce of income right here.
You need to get to lvl 75 Wood Cutting so you can cut Magic Trees. Magic Logs sell for 1k each
I think it will take about 1-2 weeks of intensive Wjood Cutting practice to reach that lvl. But it will pay off later.
As soon as you have lvl 75 Wood Cutting, Sell the Magic Logs on Forums.
Regular Logs: 20gp each
Maple Logs: 100-200gp each
Yew Logs: 500gp each
Magic Logs: 900-1400 each