Slice the baguette about 1/4 – 1/2 inch. If you slice it too thin, they won’t be able to hold the toppings. Too thick – crostini becomes all about the bread.
Brush with olive oil on both sides and arrange on baking sheet in single layer. Do not drizzle oil on top of bread because you will end up using a lot of it.
Bake at 400°F for about 10 minutes, turning once. You don’t want to overcook crostini because they will be too hard to bite. Cool crostini completely before topping.
Cover with plastic wrap on a serving tray and refrigerate for up to 2 days. I did that and honestly they did not become very soggy if at all. For guests, of course, fresh is best!