I’m standing outside Frida Kahlo’s Casa Azul in Mexico City, and I’m stumped. The neighborhood is unfamiliar, and I need lunch. Soon. But then I remember the map. I pull out my phone and see that it’s just a short walk to a ceviche stand suggested by my friend Eric. It turns out to be one of my best lunches of the trip.

That semi-serendipitous meal was possible because I had compiled suggestions from friends in a custom Google Map. And unlike a guidebook, it wasn’t weighing me down or outing me as a tourist.

Here’s how to set it up yourself: Sign in to Google Maps on a desktop and click the drop-down menu at top left. Select Your Places, then Maps, and click Create Map at the bottom. Search for addresses and business names like you would at home and add them to the map. If you want to get fancy, customize the pins with unique icons and colors—restaurants might be yellow, historical spots green, and so on.

You can save sections of your map to view offline. But if you wander out of the area you downloaded, you’ll likely need to use cellular data on the go. Luckily most carriers offer roaming plans for travel. Just remember that when you’re abroad, your phone is a tool, not an entertainment device. Lay off the Facebook unless you’re on Wi-Fi or you’ll punch through your data cap and get hit with overage fees.

Armed with my Google map, I find my way to the best bakery near my Airbnb; on one evening I’m able to bring my friends to a tiny mezcal bar with a handwritten menu. I’m new to the city but feel like I’ve been there for weeks. And anytime I discover another gem, I drop a pin, often adding notes so I won’t forget the shop’s hours or a signature dish. The best part? The map is shareable, and friends can add new pins. That means I’ll have a dozen new things to explore on my next visit. And they’ll all come with a trusted stamp of approval.