Midseason slump: It’s grimy with baked-on grease.
How to beat it: Your grill will fare best if you wipe it down immediately after barbecuing. Otherwise grease begins to set in and cast-iron grates start to rust. To clean the grates after a big cookout: Remove from grill and scrub with a grill brush and soapy water, then rinse with a hose. Replace, then fire up the grill to dry. To prevent food buildup, coat all the metal parts with a light cooking oil before each barbecue. For a step-by-step guide, see How to Clean a Grill.