Below link is a good site to learn about pumping, with tips on tweaking your settings. If interested, they will set up appointment to give personalized advice for a fee.
The book “Think Like a Pancreas” is great, and the author runs the site above (Gary Schiener), so some of the same info is in that book.
“Pumping Insulin” is also good book, by
Carb ratio says if you eat 20 carbs, you need 1 unit of insulin
Correction factor means 1 unit of insulin will decrease your BG by 17.
Basal of .3 .2 means the rate of insulin per hour that is delivered for the time block assigned to.
However, these numbers are approximations. A given time they vary, since many other factors influence your BGs, such as exercise, stress, etc. So if you just exercised, and then eat, your bg may drop if you do 1 unit for 20 carbs.
And during/after exercise, your basal rate may cause your bg to drop.
So having CGMS or frequent bg testing is best way to use pump and make corrections based on bg trend up, down or flat.
If you have CGMS, Sugar Surfing is a great book and website.