That basic structure is
A인 것이 B인 것보다 더 C하다.
A is more C than B
A: 저에게 뭔가 시키지 않으면 할 게 없다
D면 E하다
If D then E.
D: 저에게 뭔가 시키지 않는다.
Anybody doesn't make me to do something.
E: 할 게 없다.
I have nothing to do.
If anybody doesn't make me to do something, I have nothing to do.
Unless anybody makes me to do something, I have nothing to do.
B: 바쁘다
means "I am busy"
C: 눈치 보이고 힘들었다.
means "I felt uncomfortable and difficult.
Thus the whole sentence means,
"When I had nothing to do unless anybody made me to do something, I felt more uncomfortable and difficult than when I was busy.