SAN DIEGO (AP) -- If a Marine spots two men in his battalion kissing off-duty at a shopping mall, he should react as if he were seeing a man and woman. If he turns on the television news to see a fellow Marine dressed as a civilian and marching in a parade with a banner that reads, "Support Gays and Lesbians in the Military!" he should accept it as a free right of expression.

Prescriptions for those possible scenarios are being played out at Marine bases as the military prepares to allow gays to openly serve, ending a 17-year-old policy commonly known as "don't ask, don't tell." Training for the Army, Navy, Air Force and Marines began early this year and is expected to finish by summer's end. The repeal goes into effect 60 days after the president, defense secretary and chairman of the Joint Chiefs of Staff certify that lifting the ban won't hurt the military's ability to fight.

"These changes are about policy," states briefing material for Marine instructors. "The policy is about adherence to orders and behavior, and not about beliefs."

The latest round of training material asks Marines to consider their reactions to a wide range of scenarios, from seeing a member "hanging around" a gay bar to hearing locker-room jokes from others who refuse to shower in front of gays. Members of the 1st Marine Logistics Group report to class Thursday at Camp Pendleton.

There is nothing wrong with "hanging around" a gay bar, the materials state. The officer who witnesses the loud locker-room banter aimed at gays and lesbians should remind the Marines any discrimination or harassment is inappropriate.

For those who oppose the new policy, the Marine Corps says it doesn't expect anyone to change their personal beliefs. Still, everyone must follow orders.

"You remain obligated to follow orders that involve interaction with others who are gay or lesbian, even if an unwillingness to do so is based on strong, sincerely held moral or religious beliefs," the training material states.

A top-notch recruiter who opposes the new policy cannot refuse a promising applicant on grounds of sexual orientation but might be considered for another assignment and, at the discretion of the Navy secretary, may be granted early discharge.

Chaplains who preach at base chapels that homosexuality is a sin are entitled to express their religious beliefs during worship.

The Marines expect to finish training on the new policy by June 1, Gen. James Amos, the Marine Corps commandant, testified in Congress earlier this month.

Amos testified last year that permitting gays to openly serve could disrupt smaller combat units and distract leaders from preparing for battle. When he appeared this month before the House Armed Services Committee, he said he had been looking for problems that might arise under the new policy and hadn't found any "recalcitrant pushback."

"There has not been the anxiety over it from the forces in the field," he said.