Blueprints are an easy way to import complex structures into the game without having to go through the pain of designing them yourself. Luckily, Factorio and the community make it easy to import other player's blueprints for ease of use in your own game. Here's how you can import them.
1. To use blueprints, you must have researched robotics in the research tree.
2. Once you have unlocked this, click the Import String button on your hotbar.
3. Head over to factorioprints.com and find a blueprint you'd like to use.
4. Once you have found a blueprint, click Copy to Clipboard.
5. Click Paste or press Control+V
to paste it into the Import String box in game.
6. You'll now be able to drag the blueprint where you'd like and even keep it in your hotbar.