What's the easiest 100% for steel soul mode?

Funny enough, I just completed this achievement recently. I can tell you what I avoided that made it easier for me. You may choose to do some of these and trade them out if that is easier for you.

So I skipped the following:

• I did not fight Grimm, nor Nightmare King Grimm (2%)
• I did not get the last mask fragment for light from carrying that white flower to that grave (1%)
• I did not hear the Seer's final words by getting 2400 Essence (1%)
• I did not fight the warrior Markoth (1%)
• I did not complete the trial of the fools (1%)
• I did not get the King Soul/Void heart charm because I didn't trust my platforming skills in the White Palace (1%)
• I did not get the Godtuner and therefore did not do any of the pantheons (5%)

I believe that is how I did it. Also, a pro tip if you don't mind cheesing it a bit: Don't be afraid to pause and quit to menu when you get to low health. You'll restart at your nearest bench with full health.