"You can't always have a good day but you can always face a bad day with a good attitude."
It means that life doesn't always go the way we want, sometimes it gives us the happiest moments and sometimes it gives us the deepest wounds. Glee and gloom both possess the same amount. Today you are happy because everything is just the way you want but someday it might change and leave you sad. We never know what's coming next but what matters the most is our attitude towards life, the way we face it. You cannot always have everything settled and good in your life but you can always have the spirit to confront any predicament that comes in the way. You must accept the life in a way it comes to you with a positive attitude.