First of all, it’s important to understand the complete levelling process.
To level up, you must have a combination of 10 skill increases across your primary skills.
At that level up, you get to increase your stats in a range of +1 to +5.
to get as many hit points as possible.
Our first stat for increase to 100 must be Endurance.
So which skills do we not have control over.
There are going to be times when you have to use jump in dungeons etc which increases Acrobatics.
We must heal ourselves which means increases in Restoration.
Also, either of the armour skills, light or heavy.
We must have a way to kill stuff, so either destruction or one of the strength skills.
From the above, the most difficult skills to control are Athletics, Acrobatics and Restoration.
None of these can be primary skills as they are far too unwieldy.
So the Endurance primary skill is Armourer.
So we have:
Armourer, Destruction and Light Armour.
For strength, just choose whichever you like, I went for Blades for Goldbrand and Umbra.
For Intelligence, I went for Mysticism.
For Agility, I went for Sneak, mainly because the other 2 are a real pain to increase.
By using the run into a wall in a trespassing zone, i.e.
So create a custom Class and chose these skills.
For birthsign, The Mage for extra magicka.
I also chose mage skills to increase these skills quicker and start them slightly higher.
Remember, we need 30 skill increases per level up for Willpower, Speed and Endurance.
The area around Leyawiin is the capital of Nirnroot growth.
This combination gives you access to the first 3 skill stats and only those.
Continue to increase by whatever means, I did the regional mage quests etc.
Now rest and take your +5’s for Willpower, Speed and Endurance.
Now make a note of your new skill numbers and increase all 3 sets by 10 again.
Continue to rinse and repeat.
At this point I started to work on Strength.
Rinse and repeat till endurance and speed hit 100.
Now it starts to gets easy, start working on Intelligence and Agility in combination with Strength.
Pick up Security as and when.
As soon as I got lvl 10, I did Nocturnes quest for the security key.
Strength will max out next.
Continue with this until all stats are at 100.
With 100 resist, you are completely immune to all magical effects including those from staves.

Anyway, hope you find this of some use.
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