Take A33 as an example

Step1

Plug the WiFi extender into a power outlet near the router in the same room. Wait until the LED indicator of the WiFi extender turns blinking red.

Step2 

Connect your mobile phone to the WiFi network of the WiFi extender by default name: Tenda_EXT.

Step 3

A quick setup page will appear automatically and then tap Start Now

Step4

Set a login password for network security and tap Next.

Step5

Select Extender Mode, then tap Next.

Step6

Select the WiFi network you want to extend.

Step7

Enter the WiFi password of the WiFi network you selected, and modify the extender WiFi name, then tap Next.

Step8

Configuration completed, and then you can connect to extended WiFi.