How do I delete devices from my apple id?

That's a strange one, I don't know, I'll see if I can muster some help.

How/why do you want to remove them from your account ? e.g. if you are selling or giving a device away and want to unlink it from your account so that the new owner can register it to their's then you can do so via your support profile : https://supportprofile.apple.com/

A device or computer will only become associated to an account, and appear in the 'manage devices' section, if you use iTunes Match or automatic downloads on it, of if you redownload the account's past purchases on it (if you don't have any associated devices/computers then the section won't show). Have you done any of those ? You could try redownloading a past purchase on a device or computer and see if that section then shows with that computer/device listed (but if you do then it will become associated for a minimum of 90 days).

And for the hidden purchases, have you ever hidden any ? You could try hiding something and see if that section then shows : hiding and unhiding.

The 'manage devices' section is iTunes store related, so I don't think is related to your problem.

Your id shows in System Preferences > iCloud, and is only your account shown in System Preferences > Users & Groups (the old owner's id isn't still listed) ? When I've added a device to, for example, FaceTime I've then got messages on my other devices and my Mac saying that a new device has been linked to my account (or wording to that effect), but that is just for FaceTime

If you want the 'manage devices' button then you need to use iTunes Match or automatic downloads on the device or computer, or redownload some of your past purchases on it - it should then appear

I can't find manage my devices or anythin relating to that PLEASE HELP

The 'manage devices' section will only show if you have computers and/or iOS devices associated to your account i.e. you've used iTunes Match, automatic downloads or redownloaded past purchases on them. If you have then if you log into your account via the Store > View Account then you under the 'iTunes in the Cloud' section on your account's screen you should see something like Winston's screenshot. If you haven't done any of those three things on a computer or device then the Manage Devices section will be hidden

Hi, i have just removed my device from my itunes acounnt does this mean the person who brought that phone has to wait 90 days to set it up or download things or what?

Depends upon how long it had been associated to your account (it's the 'manage devices' section that you removed it from ?) - it's only if it had been associated for less than 90 days that it will have the remainder of those 90 days to complete. Even it is associated it shouldn't stop him/her from buying new items on it.

under iTune match i didn't see the manage devices option how will i find this option

The 'manage devices' section only shows if you have computers and/or devices associated to your account : View and remove associated devices in iTunes - Apple Support