Use white space to create a visual hierarchy on the page.
The default maximum page width is 1020px, but go wider if the content requires it.
Use a grid to lay out your content. To prevent long lines of text, content should sit in a column which is two-thirds of the page width.
Long lines reduce legibility, so all lines of text should be no longer than 70 to 80 characters.
Design for small screens first using a single column layout.
Optimise for different screen sizes, but don’t make assumptions about what devices people are using.