Tutorials: How to make itself an administrator?

users.ini - Setting up admins

The users.ini file in your addons\amx\config folder is where players are given admin priviledges under AMX. It contains the different levels of admin access for a default install. Below are some examples of how to set up admin access for your admins.
The first part of the users.ini file is labeled "Access Flags". These letters will define what commands your admins will have access to:

Access flags:
a - immunity (immune to AMX commands such as kick, slap, or ban.)
b - reservation (can join on reserved slots)
c - amx_kick command
d - amx_ban and amx_unban commands
e - amx_slay and amx_slap commands
f - amx_map command
g - amx_cvar command (not all cvars will be available)
h - amx_cfg command
i - amx_chat and other chat commands
j - amx_vote and other vote commands
k - access to sv_password cvar (by amx_cvar command)
l - access to amx_rcon command and rcon_password cvar (by amx_cvar command)
m - custom level A (for additional plugins)
n - custom level B
o - custom level C
p - custom level D
q - custom level E
r - custom level F
s - custom level G
t - custom level H
u - menu access
z - user

The next part of the users.ini is labeled "Account Flags". These options control how the user is authenticated:

Account flags:
a - disconnect player on invalid password
b - clan tag
c - this is steamid (or wonid)
d - this is ip
e - password is not checked (only name/ip/steamid needed)
k - name is key-sensitive, so if you name "NoIvEl" that means players can use nicknames like "noivel", "NOIvel", "nOIVel etc., but not "NoIvEl"

The format of making an admin

The format of the entry for each admin is this:

(name|ip|steamid) (password) (access flags="flags") (account flags="flags")

Admin Access by Player Name or Clan tag

This is not the best way to grant admin access. It requires the client to set a password on their end. Many players can do this, how ever many do not grasp the concept of editing config files let alone with the correct info. It's a burden on the person setting up the access and the person receiving it in the end, and there is no added security with this method over access by Steam ID.

"Noivel" "CreateServer" "abcdefghijklmnopqrstu" "a"
"[-O-]" "wacky" "abcdefghijklmnopqrstu" "a"

(Hint: Hover your mouse over the admin entries listed above for additional tips)
Above is what you do on the server's side. The client must have the password entered on their side also. To do that, create a file in your cstrike folder called userconfig.cfg if you don't already have one. In it, have the client put setinfo _pw "password" in it. For example:

setinfo _pw "CreateServer"

The password field and password should match what you have on the server. For more info on this, go here.

Admin Access by IP address
You would want to use this method only if you are connecting to a server on a LAN. On a LAN without internet access, players will not have unique Steam id's. So this method allows you to assign admin rights to your computer's address instead. If the IP is dynamic, then this could change though so keep that in mind.

"192.168.0.100" "" "abcdefghijklmnopqrstu" "de"

Admin Access by Steam or WON ID

This is the method just for STEAM version. Admin access is set up for the clients with this one line. The client doesn't have to do anything. Once you get the player's Steam ID, that's all that is needed. You don't even need a password since your Steam/WON ID is yours and no one else can have it unless your CD-Key gets out. (Use your wonid if applicable. Examples shown work for Steam and WON servers.)

"STEAM_0:1:12345" "" "abcdefghijklmnopqrstu" "ce"

Putting it all together

Now if all the players mentioned above were in the same users.ini file it would look like this:

"Noivel" "CreateServer" "abcdefghijklmnopqrstu" "a" ; Jason
"[-O-]" "wacky" "abcdefghijklmnopqrstu" "a" ; clan [-O-]
"192.168.0.100" "" "abcdefghijklmnopqrstu" "de" ; Jeff's IP
"STEAM_0:1:12345" "" "abcdefghijklmnopqrstu" "ce" ; Bigz - Mike

I like to use comments in config files and use of the TAB key keeps things formatted nicely too. Sometimes you can forget who some people are or they change their player name alot. So comments at the end of a line can be useful in adding more details about the person. Use a semi-colom ";" at the beginning of a comment in .ini files. What ever is behind the ; is ignored by AMX.
Information got from AMX Mod Setup Guide
Half-Life server administration by OLO (c)