Are you referring to the header area or the actual pattern area. You can show or minimize the ribbon but you cannot change the size of any font or icon in that header. You can also adjust what is showing in the header and that can affect the spacing to see things easier.
The only thing you can do to truly change the size of things is to set your operating system to a larger font and that can have repercussions all over the place! It's a global change that affects every app running on your PC/Laptop.