How to add user to admin group? Or How to give administrator right to user?

Step: 1 Click start button
Step: 2 type run and then press enter
Step: 3 type compmgmt.msc command and then press enter
Step: 4 locate Local Users and Groups and then select Groups
Step: 5 Now locate the Administrator group on right hand side
Step: 6 Right click the group and select properties option
Step: 7 Now select Member of tab and click on Add button
Step: 8 Please enter the username which you want to give the admin rights
Step: 4 click on Check Names and then select OK

FYI: You may need to log off and login again to take effect.