If you want to watch a video tutorial on this matter, our friend Jeff Springer has you covered! There is also a step-by-step tutorial with images below the video.
As an icon pack Developer, I got many questions from my users about how to apply a custom icon pack to the Samsung OneUI launcher. I decided to make a step-by-step tutorial for anyone who would like to change the looks of their homescreen. First things first, you will need an app called Theme Park. You can install it via Good Lock (or if you don't have Good Lock, just search for it on Google). Once you install Theme Park, you are ready to go.
Step 1: Open Theme Park and click on “the Create New” button
S.tep 2: Select a new wallpaper for the theme or stick with the current one
Step 3: Change the tab for the settings you want to change (our example is icon pack, but you can change a lot more)
Step 4: Once you selected Icon pack tab from the main screen, click on Iconpack button
Step 5: Choose the icon pack you want to apply (our choice is Vera icon pack)
Step 6: If you finished with all the settings you wanted to change (we just changed our icon pack) click on the top right button to save a theme
Step 7: Insert the name for the Theme you just created
Step 8: Wait a bit until theme is being installed on your phone
Step 9: Once the install is done, you will see your new theme inside the Theme Park main window. Just click on that theme in order to apply it
Step 10: There will be a new pop up window once you click on the theme. You can now Edit, Delete or Apply your theme.
Step 11: That’s it, once you clicked Apply, your new theme is now set. You can enjoy your custom icons in OneUI launcher!
Step 12: Even icons in the sidebar (and other places) are now themed!
The work and tools here were mainly created to solve common issues in client projects or as learning tools for myself. Although I'll try and answer any question I can't guarantee support for these tools, or even updates.