To figure out NET delta of your position you need to add delta of ALL options
Based on that number we look for an adjustment that will cut NET delta in 1/2.
Keep in mind that NET delta is different for everyone if we’re trading different size Iron Condors. For example, NET delta on 20 contracts will be different than NET delta on 5 contracts. If my NET delta is -20 then I need to buy a call with a 10 delta to reduce it to 10. If my NET delta is -90 then I need to buy either a call with 45 delta or three calls with 15 delta (45 total) to cut that in 1/2. That is why adjustments may be different for different size positions, but they all have the same goal: CUT NET DELTA in 1/2.
Hope this clears it up a bit.
P.S We talk about this in the chat during the day, please feel free to stop by and ask questions.