Can't disable admin account

I have only one account, my admin account, I would like to make that current admin account a standard user account and create a new admin account. How do I do that?

happyaid wrote:
I have created a new account on my macbook so that I can make it an admin and disable the admin status on the account I have been using.

When you say, "so I can make it an admin ..." are you saying that it is not an admin yet?
You cannot remove all admin accounts. You must create a new admin account first.

Veise, better to have TWO admins. That way if one 'breaks' you have another to hopefully fix it. You do have an admin in the person of root, but best not to use him unless essential.
To do the job create two new accounts per System Preferences. Devise good passwords and ensure you have the user names to your liking.
As you create each one, tick the little box, "allow user to administer this computer'. Now demote the current admin. Use one of the new admins to do that. Pick on the original admin open the lock and remove the tick (vide supra) from the original admin.
You must always have one admin aside from root so do the creations before the demotions. Now use the admins only for admin tasks, keeping one more or less in reserve. Use the (now) standard for browsing and day to day work. In most cases you can use an authentication box to do installs whilst logged into a standard. Otherwise drop the install file into the 'shared' user and then access that file there from an admin.