The reason why communists eventually take over a country is not because they are more organized or better equipped. Go read the history of what happened in communist countries and you'll see the pattern.
1. Communists rise up, and there is fighting, and the communists lose badly.
2. Communists flee to the woods and set up their base far away from civilization.
3. Communists recruit and train and build up their numbers.
4. Communists then invade the cities in a rapid and surprising move. The people are caught flat-footed and end up fleeing.
5. Communists mop up the small groups once they have setup themselves as a central power.
The key thing is step 2 -- you DO NOT let the communists establish themselves outside of civilization. You MUST exterminate them immediately.
When the initial fighting starts, do NOT take prisoners, and do NOT let them escape. The goal is to capture their leaders, their lieutenants, and everyone in between. Cut of the routes of their escape. Infiltrate their organization so you know what their plans B, C and D are.
One of the problems is that the harsh fighting you will employ against communist may seem unjustified to the local population. This is easily solved by holding public trials. Make sure you put a sign up on each of the executed people listing the crimes they committed. Focus, if you can, on child rape and other crimes. The more "unmentionable" the better.
That is to say, if you catch a communist and put him on trial, it's fairly easy to prove that he is a traitor and should be executed for that. Don't stop there. Find out who he has raped and killed. Get pictures of the victims if you can. It's much better to hang them for child molestation and mass rape and murder than for treason.
Additionally, if you find yourself in the position where the communists have escaped, you MUST destroy them. You cannot allow them to set up safe havens. There are some very simple ways to destroy them that don't involve burning forests down.
* Communists are incapable of feeding themselves. Cut off all supply routes, seize their shipments, etc. There will be subversive elements in your society trying to get supplies to them, so pay close attention to the supply routes and focus on keeping them starving.
* Communists do not unify except under a powerful leader. Focus on taking their leader out. When someone rises to the top, assassinate him. Then do it again and again. Keep them infighting for leadership as much as possible. Make them paranoid to trust anyone, even their closest friends and allies. Communists are WAY BETTER at killing their own communists than anyone else.
* Sexually transmitted diseases, especially ones like syphilis that cause brain damage, are great tools as well. It may be worthwhile to allow whores who are infected with such diseases to join the communist movement. Simultaneously, make sure they do not get drugs that treat those diseases. Keep in mind that virtually all communists are pedophiles, though.
I think one of the problems we have had with communism is that we have not been good at truly stamping it out. We allow communists to leave and infect other countries, and we just don't pursue them all the way to the end. Keep that in mind.
Remember Hitler was too kind. Don't be like Hitler. We know what happens when you extend kindness to these enemies who are trying to kill you.