THERE WILL BE no electronic scoreboards like those on Monty Hall's TV game shows, no gongs, no applause meter. In fact, there will be no applause at all, by decree of the League of Women Voters.

So how can we tell who wins Tuesday's televised debate between Jimmy Carter and Ronald Reagan? Try the following guidelines, which aren't so much guidelines for debating as they are for television, which is more important to the participants. In the absence of some major goof, the winner in Cleveland will be the candidate who best follows these 10 commandments.

1. Be Yourself. Those who knew Lyndon Johnson well insist that in small, private conferences he was one of the most expressive communicators to occupy the White House: quick-witted and earthy, a kidder of friends and himself. But when Johnson went on television, he usually sounded like the narrator of a third-rate historical pageant.

Many political candidates try to play-act on television, to assume a role. Maybe it's the stakes or the tension and unfamiliarity of the situation, but the result is the same: The audience quickly sees the person as a phony.

2. Be Liked. The emotional content of the debate will remain in viewers' memories far longer than the ideas expressed. Of course, there are different ways to be likeable. For example, he can show courage in the face of adversity or become the underdog at the mercy of a bullying opponent. A candidate can fail in all of his objectives for the debate and still win if the viewers at home feel empathy or sympathy for him.

3. Be Prepared. If the candidates are responding well, the answers given will seem spontaneous and unrehearsed (which of course they are not). The candidate's goal is not to be surprised. Remember George Romney's 1968 fate when he was surprised by a talk show question on why he had changed his position on the Vietnam war and replied that he'd been "brainwashed."

4. Be Enthusiastic. Not like a college cheerleader. Perhaps not even as much as Sen. Humphrey used to be. But enthusiasm for political candidates is synonymous with vitality, energy and intensity. It comes across as conviction.

5. Be Specific. The winner will back up his assertions with facts and personal experiences, not with platitudes or generalities. The back-up material will be presented narratively and descriptively, not argumentatively. He will also use the fewer adjectives and the stronger nouns and verbs.

6. Be Correct. Private memo to Jimmy Carter: It's Hubert Horatio Humphrey. Private memo to Ronald Reagan: It's Valery Giscard d'Estaing.

7. Be Anecdotal. Anecdotes help fix a point in the listener's mind. They make the candidates interesting, although a well-prepared, enthusiastic candidate who is correct in his assumptions and statements can sometimes be interesting without them.

8. Be a Listener. How well a candidate listens to questions is as important as how well he talks. Presidential debates are seldom straightforward question-and-answer exercises; reporters and candidates alike spend much of their time making speeches and assertions, not asking or answering questions.

What a candidate doesn't hear can hurt him. That's how Mr. Ford got into trouble with his '76 debate statement about Eastern Europe. He answered a different question from the one he was asked.

9. Build Bridges. These are the transitional statements that get a candidate from where he is in the conversation to where he wants to be. He doesn't evade difficult questions; only novices try that. If a candidate persists in evading a question, it will be rephrased until he looks like a criminal or a dunce.

The best debaters, however, know that it is possible to restructure a question before replying, thus removing the worst dangers. This is done by volunteering additional information or different information beyond that required by the question originally posed. "Let me put that matter into the proper perspective for you." Or, "Let us consider for a moment the larger issue here." The permutations are endless.

The best debaters also volunteer much more than the required information when he likes a question. Candidates are entitled to say everything they choose about all the topics raised, whether the initiative was somebody else's or their own.

It is possible through these techniques for a candidate actually to control an exchange by originating more interesting matters than the reporters have brought up.

10. Be Cool. "Don't get mad, get even." That good advice has been attributed to the Kennedy patriarch, Joseph P. Also, Mohandas Gandhi said it well: "When you are in the right, you can afford to keep your temper. When you are in the wrong, you cannot afford to lose it."

That's how to evaluate the debate. The loser gets fewer points. The winner gets to be president.