Hopefully, you shouldn’t have this issue with our Coconut Macaroon recipe since we add a little flour to ours.  However, if you find that your coconut macaroons are spreading the issue is likely the egg whites.  Rather than mixing them in as is, beat the egg whites separately in a bowl with a whisk until stiff peaks form.  Fold the egg whites into the coconut mixture carefully, then scoop and bake.   You can also try refrigerating the macaroons for about 30 minutes after you scoop them.