1, Below is the image of  D210 - WIRELESS POS terminal.

To begin with Press on the Right hand side Blue button for the MENU access

2, Operation settings from the MENU settings 

If you DO NOT have your password, please check with your seller 

And then ENTER your password again as shown below and PRESS the ENTER button at the bottom.     

Now on the communication page press the down arrow key.

On the communication page , click on the option WIFI PARAMETERS and click on Search.

Now the device will search for the WIFI as shown below 

Select the WIFI that you would like to connect as shown below 

Once you select the WIFI you wish to connect,
Click on the RED Cancel button on the device multiple times untill see the below message

Please wait untill you see the message WIFI INITIATING 

Once the device is connected to any WIFI , it will automatically resume to the MAIN MENU as shown below 

Now press the down arrow key from the Main Menu 

Select 2 for communciation and enter your PASSWORD again 

After you Enter the password, Press on ENTER Key 

Now on the communication menu press the down arrow key 

And Select Option 3 for WIFI PARAMETERS

Once the WIFI parameters are selected , Go to the option 1 to view the IP address 

Please make a note of this IP address on a piece of paper.

After all the above steps are completed
PRESS the CANCEL Button at the bottom of the device multiple times untill you reach the MAIN MENU.

Now Device is ready and connected to a WIFI and ready for any transcations.