Not really that hard.

First choice is which software to use.
Check out the software forum for that.
I'll recommend IS Boxer, but everyone has their own opinion.

Definitely use the Jamba addon, no matter what software you end up using.

Also go with Recruit a Friend.
Send yourself email invites from an existing account.
Then use the emailed game code to start the account.
And upgrade that account to a retail copy.
Then use the new copy to send out an RAF invite to your own email.
Chain the accounts together.
Get a lot of combinations to 60th, the more the better.
Basically go with 5x The-Same-Class, lots of times.

For PvE, the easiest will be:
1x Tank
1x Heals
3x Ranged DPS

If you want to melee, your toons will be in their opponents AoE/Cleave/Riposte range more often.
But not saying you cannot go with this set up.
You'll want to combine:
- IWT (Interact With Target), which is a game keybind under Targeting Functions
- CTM (Click to Move), which is a mouse option in Interface Options - Mouse.

I'll recommend Grid + Grid Custom Layouts + Clique for healing.
Have those three addons on each account.
Set up your party interface with Grid, so it is alphabetical (or any other fixed order sort that is the same on all screens).
Then use a "Repeater Region" to pass the clicks from any window, to your healer.
And use Clique to interpret the click you do, as a given heal on the target of whoever's frame you clicked on.
It is a lot easier to do in practice than it sounds, when you're starting.. and there are video tutorials of this.