I'm working on a project using PowerShell
I would like to know what is the best way to create a PowerShell GUI?
There are mainly two possible ways to create a PowerShell GUI.
Either you work with Windows Forms inside your PowerShell-Script and write the code for the GUI by yourself. Random Code Example here.
or you can use a Script-Editor with GUI tools for PowerShell like PowerGUI or, as I prefer, Visual Studio. Foxdeploy has a really good blog post about it: https://foxdeploy.com/2015/04/10/part-i-creating-powershell-guis-in-minutes-using-visual-studio-a-new-hope/
Using a GUI tool to create a PowerShell GUI will save you much time and many nerves. So that's the way to go.