President Reagan's advisers have scrapped a strategy of silence in dealing with Reagan's trip to a German military cemetery where SS troops are buried by focusing on building expectations for a speech the president will deliver at a former concentration camp site.

"Stonewalling wasn't working," said a White House official. "So we've now tried to make a virtue out of a mistake."

The new strategy reflected the aides' attempt to rescue their own public relations reputations as well as the president's. It called for Reagan to defend his decision to visit the Bitburg military cemetery and for his aides to predict that he would overcome criticism of it with his speech Sunday at the former Bergen-Belsen concentration camp. White House chief of staff Donald T. Regan said that "there'll be a new light shed on the whole scene" by Reagan's performance at Bergen-Belsen.

The strategy also depicted Reagan as a victim of overwrought press coverage, a theme that struck a responsive chord in West Germany, where Chancellor Helmut Kohl also has been on the defensive about the Bitburg visit.

An adviser to Kohl said there was "an air of sympathy" for Reagan among the other world leaders in Bonn for the economic summit.

White House aides took comfort from this attitude in a country where public opinion appears to support the visit overwhelmingly.

"It seemed like when we got on this side of the Atlantic, the problem didn't look as big," one White House aide said.

During the first four years of the Reagan presidency, White House aides showed considerable skill in diverting attention from other administration actions likely to produce damaging stories.

That technique was briefly an element of this week's strategy, when the White House held for a day the president's decision to impose economic sanctions against Nicaragua so that he could make a bigger splash with it by having White House spokesman Larry Speakes make the announcement in Bonn.

But administration officials acknowledge that this tactic had limited success, largely because most of the other leaders meeting here are more opposed to the sanctions than to Reagan's visit to Bitburg.

"What we finally came down to, as we always do, is the communicative skills of Ronald Reagan," said one senior official.

As in the past, these skills have been abetted by the scheduling of deputy chief of staff Michael K. Deaver, the Reagan intimate who has been widely criticized for allowing the Bitburg visit to be scheduled in the first place.

Reagan will spend only 10 minutes at the Bitburg cemetery, where he will lay a wreath but make no statement. He will be at Bergen-Belsen for 50 minutes, delivering what is said to be one of the emotional speeches of his career.

Considerable care also has been lavished on the other Reagan speech of the day, which he will make to U.S. military personnel and West Germans at Bitburg Air Base.

The Bergen-Belsen address was crafted by Ken Khachigian, who has written some of Reagan's most celebrated campaign speeches. They spent two hours in the Oval Office together before Reagan left for Bonn, and the president made revisions during the week.

As always, the central goal of the White House strategists is favorable television coverage for Reagan, who will be speaking at a camp where 64,000 persons died before its liberation by British troops in 1945.

Heather now covers the green site where the camp once stood, providing a stark backdrop for a Reagan speech focused on the Holocaust and other Nazi crimes.

"If the television gives the Belsen speech the coverage it deserves, people are going to be educated about the Holocaust," said one Reagan adviser. "They are going to feel very differently about this visit than many of them did when he left Washington."

Like some other presidents, Reagan has been quick to criticize the press when he finds himself in political difficulty. Unlike many of his predecessors, however, Reagan counts upon television to rescue him from his troubles.

This week the White House message has been carried by a procession of high-ranking officials who have been made available for each of the morning interview shows. Careful attention has been lavished on the camera placement for the networks at Bergen-Belsen for the event, which will be televised nationally in West Germany.

At first, the Reagan strategists feared that the television cameras would concentrate on the SS graves at Bitburg instead of the president's speech. But they now believe that the president's speech is so compelling that it will dominate the news coverage.

The White House remains dogged by some uncharacteristic glitches and lingering concern about Bitburg. Speakes, explaining to reporters earlier in the week how the United States had disavowed the concept of collective guilt at Nuremberg, where Nazi leaders were tried for war crimes, inadvertently said "Bitburg" instead of "Nuremberg."