If you’ve got a menu that’s appeared from nowhere and you don’t want it then go to ‘Manage Locations’ and select ‘Select a Menu’. Your menu should then disappear (theme version 3.14 on).
There are also a huge number of menu options that WordPress hides by default. Look in the top right corner for ‘screen options’ and click it. You will then see options that will allow you to easily add posts, tags, categories, links, Pages to your menus and for more advanced users CSS classes, descriptions and other stuff.
If you want simple general instructions on creating menus try http://codex.wordpress.org/WordPress_Menu_User_Guide
The following (rather complicated) instructions will tell you how to create two horizontal menus (with drop-downs) called ‘Top Navigation Links’ and ‘Bottom Navigation Links’.
Log into your site, look at the left hand side of the page and find ‘Appearance’. Click on it and then click on ‘Menus’. You’ll get taken to a new page.
On this page click the ‘create a new menu link’ near the top to add a new menu. You’ll get taken to another page where you can fill in a menu name e.g. ‘Top Navigation Links’. Click ‘Create Menu’.
Click the ‘create a new menu’ link once again but this time create a different menu name e.g. ‘Bottom Navigation Links’. Click ‘Create Menu’.
At the top you’ll now see the text ‘Select a menu to edit’ followed by a dropdown box (with a little downwards pointing arrow on the right-hand side of it). Clicking on that arrow will reveal either ‘Top Navigation Links’ or ‘Bottom Navigation Links’.
Click on whichever one you want to work on then press the ‘Select’ button to the right of that arrow.
On the left you’ll now see more more dropdown boxes comprising Pages, Posts, Links, Categories, Tags and Formats. Pressing the downwards pointing arrow on the right of each one will open it out. Select any Pages, Posts, Links, Categories, Tags or Formats that you want to have in your menu (though you have to manually create a ‘Link’, I’ve written a little more about that below) and click ‘Add to Menu’.
Little boxes will magically appear in the middle of your screen.
You can drag these boxes up or down to create your menu layout and indent them left or right to create drop-down menus (keep the left mouse button pressed to drag them).
If you want to change any details of your menu items there’s a little downwards pointing arrow on the right hand side of each menu box. Click on it and the box will open up (you sometimes have to click many, many times for this to work. If all else fails try a couple of very rapid clicks one after the other).
There are more advanced options available (e.g. adding nofollow to your menu links) by clicking on the ‘Screen Options’ tab at the top right hand side of the page.
Click ‘Save Menu’ (on the right-hand side) when you’ve finished.
If you want to add a link e.g. to your home page then you have to do it manually. Click on ‘Links’ (to the left of the page) and fill in the home address of your website in the ‘URL’ box e.g. http://www.mysite.com
Write the word ‘Home’ in the ‘Link text’ box. Then click ‘Add to menu’.
Finally you need to put each menu in the right place e.g. the ‘Top Navigation Links’ menu needs to be at the top of your website.
Towards the top left of your screen you’ll see ‘Manage Locations’. If you’re using the ‘Childishly Simple’ theme then you’ll see two more dropdown boxes beside the text, ‘Top Menu (Childishly Simple Theme)’ and ‘Bottom Menu (Childishly Simple Theme)’.
Click on the pointing down arrow on the right of ‘Top Menu (Childishly Simple Theme)’.
A little box will drop down. Select ‘Top Navigation Links’ and then click ‘Save Changes’.
Now click on the pointing down arrow on the right of ‘Bottom Menu (Childishly Simple Theme)’ and select ‘Bottom Navigation Links’ from the drop down and click ‘Save Changes’.