Before you touch the mod in question, note it's position in your current Load Order for reference.

Backup any INI or similar files for the mod that you may have modified, as a safety precaution.

(There are players with over 1000 hours in their current game who attribute it to always shutting down the game completely before loading any save, among other factors.) Some elements of a game are not saved until the game is shutdown and you don't want to risk that with your save game files. This is important to ensure you have a good complete save. You need this save file to be as clean and perfect as possible.

DO NOT overwrite a previous save slot or use a quicksave. Save using the menu to a new save game slot. Make sure you have turned off optional character modes such as Sneak, Auto-Run, NightEye, etc, and removed anything you have stored in containers related to the mod.(See 'Notes' below for instructions on accessing the TestingHall.) When in doubt, examine the mod ReadMe and/or documentation for instructions or clues, or ask the mod developer directly in a release thread. In the case of broad reaching overhauls, the TestingHall may be safest. Move to an interior space, such as a building or cave that is not in any way related to the mod in question. Wait about 15 seconds after the last message from any mod loading to permit them to finish initializing.

Load the save game you want to use as the base of your clean save.(Assumes you have a good working full save of the game, not a quicksave, which was created with the mod in question active.)

Save game cleaner oblivion