Ok let me start by saying that I am not suggesting one ought to solo. I love grouping when I can.
But if you want to solo to 60 here is how I did it, long, long ago at launch.
Roll a mage.
Load up on gear that has the suffix "of the Eagle" (stamina and intellect).
That's it. The most enemies you will usually encounter at one time is 3. Sheep one. Blow one up. Kill the third in close quarters (that's what the stamina is for, because you are going to get hit). Now blow up the sheeped one.
If you play a mage and think that you have to run anytime something is in your face, quit WoW and go play a ranger in EQ lol.
Do all the quests you can find.
You will reach 60 pretty quick.
EQ1, EQ2, SWG, SWTOR, GW, GW2 CoH, CoV, FFXI, WoW, CO, War,TSW and a slew of free trials and beta tests