While it can certainly be tempting to bring the claws out, especially if liberals engage in clear bad-faith, I personally have found far more success in reaching non-Socialists when maintaining a level head and trying to focus on bringing unity. That doesn't mean blunting my views or hiding them, of course, but it does require trying to maintain good faith and limiting personal attacks to an absolute minimum. Liu Shaoqi's How to be a Good Communist does an excellent job explaining the importance of patience and kindness with well-meaning but ill-informed people, as these are potential comrades. It also helps keep us in touch with the real feelings of the working class as a whole.
I think Huey P. Newton of the Black Panther Party explained this process very well:
I dissuade Party members from putting down people who do not understand. Even people who are unenlightened and seemingly bourgeois should be answered in a polite way. Things should be explained to them as fully as possible. I was turned off by a person who did not want to talk to me because I was not important enough. Maurice just wanted to preach to the converted, who already agreed with him. I try to be cordial, because that way you win people over. You cannot win them over by drawing the line of demarcation, saying you are on this side and I am on the other; that shows a lack of consciousness. After the Black Panther Party was formed, I nearly fell into this error. I could not understand why people were blind to what I saw so clearly. Then I realized that their understanding had to be developed.
I bolded specifically something I have noticed many comrades focusing on in this space, and as a Communist I would like to see us foster larger outreach. There will always be people who engage in clear bad-faith and insult us, of course, but the only way for the Left to win is to expand, and to do that we must put in the legwork to meet people where they are at from a place of humility and common goals.
At the same time, don't let fascists and reactionaries go unopposed, don't tone-police comrades, and don't bother with maintaining "civility." There's a large gulf between potential comrades and active adversaries, and pacifism does the enemy's job for them. Not all ideas are valid, and people should be called out for horrible views and behavior without worry of being aggressive. Racists, transphobes, homophobes, fascists, and reactionaries in general should be openly made fun of and combatted viciously.
It's a careful balance.