I have never needed to use a sliding scale for my own care, but I was intimately involved with my bride Jem's sliding scales
Actually she had 2 sliding scales one for her Novolog R. and one for Novolin "Aspart". She got these from her Endo not long after he took on her diabetes care. The sliding scales changed over time according to her condition.
One of Jem's "medical challenges" was Lupis (Systemic Lupis Erithramosis — or SLE)
another was Rhumetoid arthritus (RA). There were meds supposededly to help her combat those very painful conditions, but she could not take them. She was allergic to them all. The only medications to which she was not allergic was a cortisone shot, and prednisone. Of course these two medications were steroids and her Blood Glucose (BG) readings skyrocketed when she was on those meds.
She routinely went into 300 + territory when she was on those steroids. All we could do was wean her off the steroids ASAP and then use the sliding scales to bring down her BGs below the 200 mark.
Since she was totally blind I took on the task of reading her BG meter and recording it in her sheet for the month, and then twice a week, emailing the readings to her endo.
Then I drew her insulin up according to the instructions in the sliding scales and what was happening to her BG levels and the time of day. She was to use the Novolog NPH (about 60 U) and if her BG was over 160 (if memory serves) Novolog R the first thing in the morning. I was to draw up a specific amount of R if her BGs were higher than 160, a higher amount of units of R if her BGs were over 200, and the sliding scale stopped at 300 to 350. If her AM BGs were over 350 we were instructed to take her to the ER.
Then her noontime reading she was to use the Novolin Aspart (ultra fast acting). again using the escalating units according to Dr's separate instructions for the Aspart.
What I recall is that Jem's sliding scales were SPECIFIC to her. The Endo calculated what she should be able to take, and when something in her condition changed I was to notify the Endo, and sometimes he'd re-calculate it and give us another different sliding scale.
So you'll need to get an Endo involved in your care to get a sliding scale specific to you. This is not something I'd recommend for you to try on your own.