I'm actually currently 35 runecrafting, and crafting waters atm. You make some profit, like 1.2K/trip, and it's fairly fast, especially if you have many amulets of glory (4).
If you are a member, easily the fastest method is doing fires with rings of dueling. You will lose money, but in the long run, the money lost for it is only a few 100k. Additionally you can start doing double laws faster.
yeah i agree with everyone saying fires... get a ring of dueling tele to duel arena then make fire runes then get ammy of glory (or preferred banking method) deposit fires and withdraw more essence
Sports Bettor - DM me if you have credit accounts.
I'm fairly sure I made cosmics to get through these levels. Although it was quite fast, I don't think it made much profit (if at all). This was a while ago so things might have changed.
Buy 135 rings of duelling(8) and 25k essence. Tele duel arena, fires, tele castle wars for bank, repeat. You'll probably need more than 135 rings and 25k essence, but it's a good start. If you're f2p, I have no idea - sorry.