You should invest in a spud, I've been using mine a bunch this year so far, basically a big metal spear that you can 1. cut holes in ice 2. open up your frozen holes or holes used a previous day 3. make holes bigger for when you pull the big hogs in and your hole isn't big enough
If you don't have a spud, you could bring your auger, or maybe a spade shovel/garden edge/other sharp lawn tool...
If the ice is clear it is stronger than when its clouded. I walked out on a pond today, cut a hole with the spud and it was about 3" of clear ice. I walked all over the main basin checking ice thickness, all about the same. I don't think I would feel safe with much less, but this ice wasn't making any noise and felt real solid.
Definitely stick close to shore at first...then move out further. Don't forget to bring ice picks to pull yourself out if the ice does give out. I've heard of people wearing life jackets during early ice too.