Flying in the Midwest farm country of the USA I find the vast majority
of thermals by simply blundering into them blindly.

Below 1500AGL ground clues MAY help you find lift but just as likely
not. In rocky mountainous terrain it's a different story.

Determine what altitude is half way to cloudbase (if there are
clouds); Below that ignore the clouds and just go, above that the
clouds MAY help you find lift.

Real cloudstreets DO exist as do lift streets with no clouds. Keep an
open mind at all times.

Many people fly too slow in sink or even turn in sink trying to decide
what to do. Even at 800agl if the vario says 500 or 1000 down go FAST
and go straight. You are much more likely to hit a thermal on your
way to your landing field than if you fly around maneuvering slow.

Fly SLOW in lift or zero sink. Pull back on the stick to min sink and
do it immediately. Many people turn too shallow and too late in
thermals. Circle just about as tight as you can fly slow in most
thermals for the best climb rate.

Keep a positive attitude. Keep a couple landing fields in sight but
keep a positive attitude. Many XC flights have been saved on
downwind. Once you turn base give it up. Hear the theme to Star Trek
in your mind and boldly go where no one has gone before.