A file called TeamViewerQS should be downloading to your downloads folder.
When the download completes, Double click the file to extact the application.
Now Run the application by clicking the Blue Teamviewer Icon
The Teamviewer QuickSupport software should start automatically and provide you with an ID number.
Give this ID your technician so he can log in to your PC and see your screen and control your mouse and keyboard, and you can begin to discuss and diagnose your problem.