Lighten up your text if it looks a little on the heavy side

The smaller the font size, the more generous the line height
As your font size decreases, increase the line height for better, all-round legibility.

Choose a Base Colour, and then use Tints & Shades to add uniformity

Always make your ‘Call to Action’ the most prominent item on the screen

Add an extra visual aid to your Form Errors
Adding an Error Message close to the action that the user has just taken can be a simple, but helpful, extra visual aid for when they’re filling out Forms of any kind.

Give Prominence to the most frequently used action in a Menu