First make sure you are signed into Google Chrome and use the same account on all devices that you want to sync to, you can do this at the top of the settings page, by default Chrome will sync everything including bookmarks but also under Sign in on in the settings is Advanced sync settings... check this to make sure it is working. Also in Google Chrome click on the star to save or check a bookmark you can edit where it is saved
In Firefox go to the start page, at the bottom of the screen there is a button to sync click it and create an account this is similar to Chrome but Chrome will use your Google (Gmail) account