So how do you fix Everton?
Like a poster above said, its getting your recruitment right, which means you need a stable team of football people in positions to make decisions.*
Right now it seems that there's an owner acting on whims, "I want that one, now that one, now that one" when it comes to managers. Who then come in "I want that one, that onw, that one, get rid of half the team" when it comes to players, only with an ever decreasing budget.
No plan. No consistency. Just stab in the dark decisions that have lead to a poor manager in charge of a mish-mashed team.
There's something off, and until it's fixed, it doesn't matter who sits in the dugout. Give it Dyche until the end of the season.
*I know Chelsea did this for years, but they paid top money, something Everton can't do.