It takes 10 full minutes at a hard rolling boil to consider a jar sterilized. At this point in my canning life, I don't even remember what all the experts recommend for sterilization of canning equipment. I'm just going to tell you what I do: If something is going to be canned 10 minutes or less, I sterilize the jars in the canner first and fill the jars with hot product. This is a rare occurrence. I have used it for jams, jellies, and pickles. To be quite honest, I have been known to process my jams 12 minutes just to not have to sterilize my jars first. IF I were fast enough to do an open kettle processing, I would sterilize the jars for that too. When I'm pressure canning, I don't sterilize jars at all; clean is good enough. Everything inside that canner is going to heat to 240 degrees and for alot longer than 10 minutes, I believe that's adequately sterile.
Your work area and all the equipment needs to be clean from the start. This means that your canner needs wiped inside and out with hot soapy water. Your jar lifters and magnetic wand need a run through the dishwasher. I have multiple canning funnels just because of this; I can switch filling different products on the fly without having to wash the funnel. I always wipe down my counters and stove an extra time before I start working.
I usually choose to cold/warm pack my products over a hot pack. This saves me from getting my klutz self burnt and my food from being overcooked. It also means that I start over each canner load with fresh water; p.c. or w.b. If there was any siphoning, that gunk is not going onto the next batch of jars. This uses more water and takes a few extra minutes in the initial heat up of the canner. That doesn't bother me as I can work more safely for myself.
While the canner is running, I'm doing dishes and washing kitchen towels and wiping down the counters where I'm done working or I've made a huge mess. Then, when I'm all done, especially if it's been a marathon day and I'm pooped, I can turn off the canner and head to bed for a few hours before coming back to take the jars out of the canner. We will cover flat sour another day.
Happy Canning!