To avoid getting lost, you can say:

"I'll make sure to follow the map/GPS/directions."
"I'll ask for directions if I'm not sure where I'm going."
"I'll make sure to take note of landmarks or notable places along the way."
"I'll bring a map or use my phone's navigation to guide me."
"I'll try to remember the route so I don't get lost on the way back."

Alternatively, you could simply say "I won't get lost" or "I won't let myself get lost."