There are two sure ways to get Beau to come to your island. The first, and possibly the easiest, is purchasing Beau’s Amiibo card. When you scan his Amiibo card into your Switch, as long as you have the town hall and the campsite, Beau will show up, and you can invite him to move in from there. The second way is to find a friend who has Beau on his or her island. You can make friends with Beau by visiting that player’s island, and he may decide to island-hop from there. However, most players enjoy having Beau on their island, so it might be hard to find someone willing to let him go!