How to use the Lion?

Been playing 40k for about 6 months now, and I’m getting relatively experienced. I have my first tournament coming up, and I’m bringing the Lion as the center piece to my army. I havent had much success with him in the past however, so I’m wondering what are some good strategies for the primarch? Should he dominate center of the board, take flanks, be aggressive or play around other units? Thanks for any advice!