How to add a banner at top for sales or announcements

How to add a banner at top for sales or announcements

Hello,

I am trying to create a banner at top, which is gonna remain there above header. 
I tried to use message bar, but it comes with an agree button, and on click it disappears. Instead o want to use a banner for a promotion, sales etc. How to create it and keep it above header?

    Nederlandse Hulpbronnen