Introduction
Fallout 4 is a great game with and without mods. Mods are here to enhance what mod authors enjoyed about the game or remove what they didn't.
Just as with planning your load order for actual play, plan each test by ensuring you've installed a mod at the appropriate time and with any dependencies.
Play at least one time on vanilla.
How do you know what to enhance or alter if you've never played the game?
It is your game, not someone else's, and they have no power over how you play. While sharing load orders, game advice, and character builds are fun, determine what it is that you'd like to see changed, enhanced, or even removed to make your game unique to you.
Set Up Your Testing Environment
Clear your reserve space
If you are an Xbox player, start fresh by clearing your reserve space of all mods and Creation Club creations. This will clear any remnant data from mods that may have been removed improperly from the last playthrough. Clear your cache to remove any temporary data and do a reset of your Xbox to complete the process.
Rebuild your database
If you are a PlayStation player, if you haven't defragged your machine and rebuilt your database in a while, this is an excellent opportunity to do so.
Manage Your Saves
Turn off autosaving, and do not use exit save or quicksave while testing.
Why?
The game only stores three autosaves. They are very easy to overwrite if you have not disabled autosaving in the Pip-boy. The game only stores one exit save and one Quicksave. Exit save and quicksave are overwritten each time you use them.
You'll be able to keep up with your saves more easily if you manually save (create a hard save) each time.
When exiting the game, go to a different cell first so that when you re-enter the game, the data will load in properly, then exit by opening the Pip-boy first.
Create a Series of Clean Saves
When the game loads create a series of saves at intervals of sixty seconds. PS4 Players should be able to rename these saves. PS5 players do not have the same amount of control over their saves as PS4 players. Xbox players will need to manage them by keeping up with the timestamp on the save.
Keep up with what you download
Do you have mods you aren't using but are still listed in the Library on the Bethesda.net "My Mods" page? Now is an excellent time to clean those up. You can only view 98 mods in total from inside the game mod catelog unless you've extended the UI with a mod like Ugh. Mods Manager Cap. But if you aren't using a mod, there is no reason to keep it in the Library. Save it to your Favorites instead so you can come back to it later. You can order by favorites on the website and in the in-game manager.
The Bethesda website's "My Mods" page does not show mods in load order. It is ordered by the last update date. It, unfortunately, cannot be used to keep track of mods outside the game, and if you could, it is not shareable with others if you happen to find a mod you enjoy, load order you're really proud of, or need assistance with your load order.
The Load Order Framework is here for a reason. It gives you a way to manage your load order outside of the Xbox in-game mod manager and easily share it with others. Copy the blank Framework template to your Google Drive, and use the first tab to make additional templates for your testing purposes. Use it to plan and test your load order. Instructions for all devices can be found on the link provided.
Read the Descriptions
Mod page descriptions serve as both the marketing material and information a player needs to make a load order decision.
Not all descriptions are created equal. If there is not enough information to make a decision, then it is not advised to download the mod. Mods that were created prior to 2018 only had 2500 characters to use on the Bethesda.net website. Now, there are 6500 characters but they must be manually edited by mod authors from the website and not from within the Creation Kit.
If the mod is a port, read all documentation from the original mod site it was ported from before downloading.
Does it need to be installed before or after the Prologue? Does it require another mod to function properly? Just as with normal gameplay with mods, waiting too long for quests to run may cause the mod you're testing to break if it needs a quest that runs and stops before you got your hair did.
Know What Mods Do Before Committing to a Real Game
Enable and test mods individually before testing altogether. You need to know what a mod does in its vanilla state before you can add others.
Asking on the Parent Server can help you save some time; however, there are over 20,000 mods on Bethesda.net with new mods added daily. There's no way for one individual to know what everything does. We're here to help and give you a community to support you when you're frustrated, but you still need to see for yourself what it does so you can judge whether or not you want to keep it in a main save.
Advanced Troubleshooting
Most crashes occur due to load order conflict.
If you've encountered crashes while testing (or while playing) and think there might an issue with a mod, a standard, but advanced method of troubleshooting is dividing your load order in half and doing a binary search of the conflict.