When we’re striving to excel at something, how we show up is everything. You could be an employee looking to nail a key presentation. Or running onto the field for a must-win match. Or debuting a piece of work as an artist. Whatever our pursuit of excellence, we each need to show up mentally, not just physically. That’s why this month’s featured collection of exercises has one overarching theme: being at the top of your game in your chosen field.…