Let's start this tool with this command:
[root@desk mythcat]# dnf install qt5-designer.x86_64 ... Installed: qt5-designer-5.12.5-1.fc30.x86_64 qt5-qttools-libs-designercomponents-5.12.5-1.fc30.x86_64 Complete!
Follow this video tutorial from my youtube channel:
[mythcat@desk ~]$ designer-qt5
You can preview your work with Ctrl+R keys.
After you finish with the project then save the file with this name: mytest.ui.
The next command to create your working python file named mytest.py.
Use this command with the -x option creates the main section to the my.py file that will allow us to test quickly whether the GUI looks as we intended.
Now you can run it to see the output:
[mythcat@desk ~]$ pyuic5 -x mytest.ui -o mytest.py
[mythcat@desk ~]$ python3 mytest.py