train at gnome strong hold till 35..
after that do the barcrawl (head north of baxtorian waterfalls to barbarian outpost.. Talk to the barbian outside entrance, he will give you a card, you must visit the bars listed on the card, then return to him after visiting them all.. Rsbandb has a guide for this, so does runehq..
Once you can enter, train there till at least 40 agility, take lobs, swordies, or sharks, and just do the rope swing over and over, or the whole course.. I found it very fast doing rope swing, 20 exp per swing, and at 35 agility i barely failed. at lvl 40+ head off to karajma, in birmhaven there is a dungeon on the west side gate. Pay 200 coins to enter, where boots of lightness, and take 27 slots of the best food you can get. Work on getting tickets, it will get you lvls fast.
cashing in tickets, at the entrance to the agility dungeon in birmhaven, one of the npcs there will trade your tickets for agility exp..
the more tickets, the more exp. also you can trade for toadflax (a herb) or if you have 800 tickets, trade for pirates hook.