First you have to know how to write a bar. In order to write one, you have to know what it is. What is a bar? Basically a bar is a way to divide a verse into segments. Example the verse is: I love to write and I can write all night, because writing is my thing and it buys me bling. This is what it looks like with bars added: (bar) I love to write (bar) and I do it (bar) all night (bar) because writing is my thing (bar) and it buys me bling(bar) You notice at the end each line or bar the words ryhme. The simplies way is to think of each individual bar having two parts and between the parts you can add the beat. FYI drum and bass beats are pounded twice per bar. (drum drum/bar) .