One of the easiest yet most powerful ways to get comment karma is to study the different threads on different subreddits in the same niche.
You would notice that the same topic keeps coming up again and again because different people at different times ask the same question.
You would also notice that certain answers get a lot of Karma because it seems to be the conventional wisdom.
It seems to be the generally accepted "correct answer" for that type of question.
Make note of this.
The next time the same type of question comes up, you basically come up with your own version of "the accepted" answer.
9 times out of 10, people will give you an upvote because you're giving them the answer that they are most familiar with, that they are not threatened by, and that they are expecting.
Now if you were to give them the truth or you give them the truth dressed up in a weird way, all bets are off.
From my experience, they either welcome you with open arms and upvote you to hell, or they just ignore you.
Worse yet, they downvote you like crazy.
Take it from me.
Study your niche.
Study your subreddits.
Read the threads carefully.
Pay attention to the patterns.
Pay attention to expected answers and what the community sentiment is, and just copy that.
Of course, you have to use your own words, and you have to use your brain.
But if you play how the community wants you to play, you will get rewarded.
The dirty truth about Reddit is that it is riddled with groupthink.
Herd mentality runs amok in that place.
If you're just a happy little sheep, ready, willing, and able to go along to get along, you will be rewarded.
On the other hand, if you're the nail that sticks out, 9 times out of 10, you will get hammered down even if you are preaching the truth.
I know it's sad but it's also reality.