I do not think and I do not expect Crystal palace to do much about this match. Crystal palace doesn't have the capacity to pull surprises in this final, rather they will be the recieving end.
Liverpool is clearly the favourite as they have a more formidable squad than Palace. Besides they have things to prove this season. They have many expectations from us due to how much they spent in the market. So, they should start with this one to make us believe they are serious for business.
It is not good to count anyone out, but Palace being demoted from Europa league is a very big demotivation to perform.
In the game of two, one is expected to win. All hands are pointing at Liverpool to win against Crystal Palace easily to lift the Community Shield trophy in four days from today. Although we never know what the finals would be like anyway because we have seen what has happened last season in the FA Cup, the Europa League, and the FIFA World Cup, that the teams we never expected to lift the mentioned league trophy.
Liverpool, I know, wouldn't treat Crystal Palace with less hand, and Crystal Palace, in the same vein, will give their best to match up with Liverpool's strength. Let's see how it goes anyway whether another surprise will hit us again in the world of football.