A clean sliding glass door makes a bigger difference than you'd think. Here's the most effective method, plus the mistakes most people make.
Use a crevice tool to vacuum dirt and debris from the bottom track of the door.
Spray glass cleaner or vinegar solution and wipe with a microfiber cloth in long strokes for a streak-free finish.
Use an old toothbrush dipped in soapy water to scrub the tracks. Wipe with a clean cloth to remove debris.
Wipe everything with a clean damp cloth, then dry. Make sure tracks are completely dry to prevent rust.
Apply silicone-based lubricant (not WD-40) to the tracks for smooth sliding.