Hello The presets I have uploaded are now obsolete. How can I delete them? Thanks

You cannot delete them, you can however make them invisible by going to the preset's page and unchecking "visible."

-If it's an update to an original preset, why not just edit the original post to include the update? -If it's a whole new thing, just make the new preset page and link it on the old one explaining that the times have changed, but no need to remove the old one in case someone has preference to it. Zomie's not wrong, either, but this is my take on it.