How do I deal with much larger opponents in BJJ?

Training with larger opponents is one of the best ways to develop technical BJJ because you simply cannot rely on strength. From guard, use open guards that keep distance like spider, lasso, and collar-sleeve rather than closed guard where they can smash you with pressure. On top, be quick to establish control and use knee on belly rather than trying to hold side control against someone who can easily bench press you off. Avoid the fifty-fifty position and leg entanglements where weight can be an advantage. When passing their guard, speed passes are generally more effective than pressure passes against larger opponents. Chokes tend to be higher percentage against bigger people than joint locks because they are harder to power out of. The most important mindset shift is accepting that you will not be able to hold positions the same way against a 250-pound opponent as you do against someone your size. Use movement, transitions, and submissions over static control.