lvl 1 - 20 : Youll be stuck on trainee Island until around 13 - 15 so just follow the NPC quests until you hit 20.
lvl 20 - 30 : Just do the quests from all three towns until around 30, the quests may seem boring but its worth it in the end, if your having decision trouble on the flow of quest choosing then you could do 2 levels worth for one town then go to the next and so on =P. Try to get to to JB lv 20 ASAP, youll want Dual Weild quickly.
lvl 30 - 45 : Go train in Moonlight ruins, try to find a party there or duo with a kahuna or Cleric, stick to cont 1 or cont 2 till 35, from 35 to 40 grind in Oforias room but do NOT get key happy and try to attack Oforia, its a death wish. Stick to cont 3 or cont 4 till 43 or try to get a good Oforia party if your lucky, from 43 to 45 grind in Abhuvas room, if you can try to find an Abhuva party you can join, he's good exp trust me.
lvl 45 - 65 : Go to Lost Mines and train there, stick to cont 1 till 50 then cont 2 till 55, cont 3 till 58 and finally cont 4 till 65. Primal Scream and Taranida are much stronger than Oforia or Abhuva so do not try to make a party. If you do want to fight them however, make sure the following things: MUST have 3 clerics or 2 rappelz if there REALLY good, all MUST be 60+ for Primal, 65+ for Taranida, only have one attack them, all other attackers stay back and use a bow or range skills.
lvl 65 onwards : Go train in Crystal Valley, getting there is no walk in the park btw, once you reach Crystal Mountain I recommend you get off your mount, turn on quick pace and use a wind pot and run to CV, your probably wondering why ive said this, well for a few reasons : You dont have the mount pause at the portal, If you get hit and you dismount there is a slight pause in which mobs can swarm in for the kill and most importantly, if you were using a mount and were knocked off you probably havent speed buffed YOURSELF in which you can pretty much say goodbye. stick to cont 1 till 68, cont 2 till 72, cont 4 till 75, cont 3 75+ (for some odd reason cont 3 has higher mobs), as for Crustalino and Likirius, the same rules that apply to Primal and Taranida apply to them, but most must be r4.
Tips:
Chips: Try to always contribute chips, but since you need rappelz rupees split the laks in half, if possible get an upgraded Chaos Necklace.