How to install .gwd watch faces on Samsung watches

See how to install in a youtube video (it's better if you don't like reading a lot of text)

Requirements:

-Samsung Watch (obviously)
-A computer
-Your phone
-The watch face in .gwd format
-An internet connection
-Your brain (it should be turned on)

Installing and opening up the .gwd file

First of all, you have to install Galaxy Watch Studio by clicking here. Once you installed it, you have to open the .gwd file with Galaxy Watch Studio. Open Galaxy Watch Studio, you should be on this window :


Now, you have to quit the "New Project" window to have access on the workspace, once you did it, you have to click on "File" which is at the top left of the window, then you click on "Open" (or you can click Ctrl+O without opening the File dropdown button).
You will be redirected to the file explorer, you open the .gwd file and now you can see the watchface in the workspace.

Run the watchface on your Samsung watch

Now there are two options : Connect your watch device to a Host PC (you need a USB cable and it only works on Android phones). or Connect your watch to a Host PC via Wi-Fi (it needs a wireless access point).

Connect via SDB over BT

Setting up the Host PC.

a. Connect your phone to Host PC using a USB cable.

Setting up the Watch device

a. Turn on the Bluetooth.
b. Turn on debugging mode.
-Gear watches : Settings > Gear info > Debugging
-Galaxy Watch : Settings > About Watch > Debugging
c. Rebooting the device might be needed.

Setting up the phone

a. Turn on debugging mode.
-Settings > Developer options* > USB debugging
*To show the developer options on a Galaxy mobile, go to Settings > About device > Software info, then tap the Build number until "Developer options enabled" appears on the screen.
b. You have to install SDB over BT (according to the Samsung instructions, they ask you automatically when you start to use the Galaxy Watch Studio), if it's not the case, you can download it by clicking here.
c. Open "sdb over BT" on your phone. Tap "SELECT DEVICE FOR DEBUGGING" button and select your watch to connect.

Connecting to Galaxy Watch Studio

a. Open the Galaxy Watch Designer and click the Run on Device icon on the toolbar.
b. Select Your Phone, this will start searching Watch devices with in subnet.
c. Within a few seconds, you will get the results.
If this is the first time to connect, you will see the below popup on the device. This is for the security. Select ok to allow connection.
This popup will not be displayed in subsequent connections.
d. Once the connection is completed, you can select the device to start the installation and run the Tpk.

Done, you have now the watchface in your watch

Connect via Wi-Fi

Setting up the Host PC

a. Connect the Host PC to the Wireless Acess Point via UTP cable or Wi-Fi.

Setting up the watch device

a. Turn on the Wi-Fi.
b. Turn on debugging mode.
-Gear watches : Settings > Gear info > Debugging
-Galaxy Watch : Settings > About watch > Debugging
c. Reboot the device

Connecting the watch to the Wireless Access Point through Wi-Fi

a. From the Wi-Fi menu of the watch device, find the Wireless Access Point and connect to it.
b. Once connected, find the IP address that the watch device received from the Access Point via DHCP. This IP address will be shown during the connection in the Galaxy Watch Studio.
You can get this IP address by checking the information of the access point the watch device is currently connected to.
c. Now you are ready to connect to the Galaxy Watch Studio.

Connecting to Galaxy Watch Studio

a. Open the Galaxy Watch Designer and click the Run on Device icon on the toolbar.
b. Select + button and Enter IP address.; this will start searching watch devices with in subnet.
c. Within a few seconds, you will get the results.
If this is the first time to connect, you will see the below popup on the device. This is for the security. Select ok to allow connection.
This popup will not be displayed in subsequent connections.
d. Once the connection is completed, you can select the device to start the installation and run the Tpk.

Troubleshooting

If Scan devices doesn’t give any results.
a. Check if Debugging is ON.
b. Wake Watch up and retry.
c. Reboot the watch and retry.
d. Check if watch and Host PC are connected to the same Access Point.

Done, you have now the watchface in your watch
Source: Samsung instructions from this PDF file.

Youtube video