I'm having trouble figuring out how to change seats online. In august im taking a big trip. Part of that trip includes DEN-LAX, on a 2 class 777, and LAX-SAN on an emb120. SAN has such a great view of the landing and I wouldn't want my mom to miss it and this is the first time shes been there in 25 years. How do I change seats online to get her a window seat on my LAX-SAN flight?