''I love your life,'' Garry Shandling gushes to Warren Beatty in Love Affair. With this typical best-friend patter, Shandling joins the ranks of recent romantic-movie sidekicks funny, down-to-earth guys (Rob Reiner in Sleepless in Seattle, Bruno Kirby in When Harry Met Sally) whose job is to provide light moments and cater to the star without upstaging him. Now that he's got expertise, we asked Shandling to be a pal and give us his tips on how to play the best friend.
*''Make sure you get in the movie. If you're not in the movie, don't worry about playing the best friend. You'll never pull it off.''
*''Have a best friend in real life. Otherwise, you have nothing to draw on. It helps if your real best friend resembles your best friend in the movie. I had a best friend who resembled Warren Beatty. At least he resembled him years ago. Last time I saw him, he looked more like Annette Bening.''
*''Take a lot of acting lessons. You have to be a better friend than you could ever be in real life. I've lost all my previous friendship roles to Rosie O'Donnell, who plays a much more believable friend than I do.''
*''Attempt to actually become best friends with the person who's supposed to be your friend in the movie. This makes for much less acting. (However, you risk the danger of hurt and rejection, and of being obnoxious both on screen and off.)''
*''Make sure you're not better-looking than the star. This is one area I did not fulfill.''
*''Be the funny one. In Love Affair, I tried to add a little humor wherever I could, although I firmly believe people cry right through my scenes.''
*''Don't get the girl on screen. The best friend gets the girl off screen, which I prefer.''