STEP 1: Create all the pages you need or that you would like to appear on the Menu... To learn how to create a custom page, Click here
STEP 2: Now navigate to Dashboard > Settings > Layout. You should have something similar to the image below.
STEP 3: Click on the Add a Gadget link just above the Blog Posts section...
STEP 4: In the Add a Gadget popup window that comes up, scroll down to find, the pages gadget.
NB: If you already have the Pages gadget added to your blog, Just drag the Pages gadget column up to the top under the header... And you have your menu. Otherwise continue with the steps below.
STEP 5: After Selecting the pages gadget, you would be redirected to a page where you can customize the look and feel... Click save and you've got your menu bar...
NOTE: The gadget must be under the header gadget or above the Blog Posts to work and not sideways... Your end result should be something similar to this
Dont forget to drop suggestions, questions or comments in the comment box below. thank you