How to Play the "Four Swords" by Yourself for Game Boy
- 1). Insert the "Four Swords" game cartridge into your Game Boy Advance or GBA SP, and turn the system on.
- 2). Press "Down" on your Game Boy Advance's D-Pad to select A Link to the Past Mode, and press "A" to launch this mode.
- 3). Press "A," and input a name for your character using the on-screen keyboard. A Link to the Past Mode saves your character's progress so you don't have to play all in one go.
- 4). Place the cursor beside your character's name, and press "A" to start the game.
Source...