first of you need a good dds converter which you can download paint net BUT if you use photoshop i highly recommend useing this plugin install in it
https://github.com/GameTechDev/Intel-Texture-Works-Plugin/releases
it has readme to how to install and use it if u have photoshop already thats good if not then tell me to send u my version its old about 240 mb its better than the 3 gb the newest version in terms of that and its portable when ur done put ur dds files in iwi convertor and done
and do this when ur about to do save as part dds https://forum.plutonium.pw/assets/uploads/files/1654875113637-dd07fcc6-51ad-43ad-9601-7d46e840cdd9-image.png