try (one's) damnedest

try (one's) damnedest

To put forth the maximum amount of energy or effort toward some task or goal. Money is a little tight at the moment, but I'll try my damnedest to be there for your wedding! I'm trying my damnedest to get a passing grade in this class.
See also: damnedest, try
Farlex Dictionary of Idioms.

do/try your ˈdamnedest

(informal) try very hard; make a very great effort: He was doing his damnedest to make me feel uncomfortable so that I would leave.
See also: damnedest, try
Farlex Partner Idioms Dictionary
See also:
  • damnedest
  • do (one's) damnedest
  • do your damnedest
  • do/try your damnedest
  • do (one's) darnedest
  • break a sweat
  • bend (one's) efforts
  • bend your mind/efforts to something
  • apply oneself to
  • apply to