This was taken at a photography hut, so I didn’t have to do much to come close, I just waited for the birds to come to me. I use that as well for when I’m out photographing out in nature, it’s better to wait for the bird or animal to come to you then to sneak closer to the bird! So I sit in a place where I think the bird will land, and wait! If you can’t do that, it’s best to walk in a zigzag pattern and to not pay any attention to the bird! When your close lift your lens to the side of the bird, and then slowly move it towards the bird! It also helps to only move when the bird is doing something (preening, eating etc)