Packing the perfect bag is essential for backpackers. Whether its a trip around the world or a weekend in the woods, carrying lightweight gear is ideal. But how do you decide what to take and what to leave behind?

“I take only the essentials and if I really need something, I buy it. It’s not that hard to find medicine, clothes or an umbrella overseas. I also try to stick to the same climate during my trips to avoid carrying lots of different clothes,” travel blogger Nomadic Matt wrote in a blog post. 

The blogger has been traveling the world since he was 23 years old, and has published a list of items that he packs when traveling. Among items that are heavy, but he deems necessary are dress shoes for going out to places that are not sneaker friendly.

Ryan Gargiulo, writer of the travel blog Pause the Moment, saves space by stuffing his socks and underwear into his shoes. He says both men and women should be able to fit 4-6 pairs of socks in a shoe. Men can fit up to 5 pieces of underwear, while women can probably fit up to 10.

“This method not only utilizes the would be empty space inside of your shoes, but it also saves you some serious space in your luggage or backpack,” writes Gargiulo.

Although space can be an issue, don’t be afraid to carry a small first aid pack. Stephen Schreck, writer of the blog A Backpacker’s Tale, carries an EpiPen in his first aid kit.

“You also need to carry anything that will help you manage your allergies or any medication that you might need to take. This will make you prepared if you have any minor medical problems. I suggest building your own first aid kit as it will be specific to your needs,” Schreck writes.

For some travelers, it’s a right of passage to share what’s in their bag. Click on the slideshow above for a sneak peek into travelers’ backpacks.