The Woodcutting ring is made by right-clicking the uncharged ring and selecting "Charge" within the Woodcutting skill plot area of the clan citadel. The ring requires a Woodcutting level of 40 to be charged in the Woodcutting plot. It gives an additional 50% Woodcutting experience to any you earn until you have gained a certain amount of experience, determined by your level and the tier of the woodcutting plot, after which it crumbles to dust. A new uncharged ring can only be obtained after this one has been used up. If you die and the ring isn't protected it will not appear at your gravestone and you will need to get a new one at the beginning of the next build cycle.
The player does not need to have the ring equipped to function. Simply having it in inventory increases experience and decreases the ring's charge.