Note all your essence, grab a stack of cash, put on a nature tiara and take out 26 un-noted essence. Grab maybe 7-8gp per essence. Take the gnome glider to Karamja and run to the nature altar, and craft the 26 essence. Exit the altar, and head northeast until you find the general store. Sell 25 essence (preferably like sell 10, buy 10, sell 10, buy 10, sell 5, buy 5, just because there are people who steal essence) and buy them back. Don't sell 26, because one space was taken by the nature runes you just crafted. Walk back to the altar and repeat. There's a "guide" I guess... Or that's the best way to do it without the abyss.