Keep an eye on:
Where you are
Where you're going
The weather
Where you have to go should it become very quiet all of a sudden
How much fuel you've got
How quickly you're using it
How much fuel you need
How much fuel you might need should 'anything' happen
How much fuel you want to take on the next sector
The weather
How all the systems are performing
How the crew are performing, including yourself
What other aeroplanes are doing, should be doing and aren't doing
Speaking to ATC
ATC speaking to you
Speaking to OPS
Dealing with passengers
The weather
Dealing with technical problems
Dealing with technical problems you've NEVER even seen or heard of before
The weather
What IF?
What IF?
What IF?
Etc..
Etc..
Etc..
Do all that and more and you'll be glad of the automation. And you probably wont get bored. Failing that try
this
You don't really need a working relationship with your colleagues, although you will develop one in time, thanks to SOP's and CRM.