If you have a camera phone take a picture of the rules so it on that just incase the one in your pocket gets lost. In fact I make a copy and laminate it and put in your wallet and have the original tucked away in your binder. Make sure that the knife is 3in or under a lot of knives are advertised as a certain length but they aren't measured from tip to handle which is how I know they measure it in California and probably other states when it comes to legal limits but they instead measure the actual usable blade length. My ka-bar dozier is advertised as 3in which is why I bought it but it is actually closer to 3.1in which makes it illegal in 2 neighboring cities, had it been 3in it be legal. Kershaw on the other hand measures tip to handle and even state it in their FAQ on their website and I confirmed their measurements on my kershaw tremor to be accurate.
If you want a knife that isn't intimidating pick up a SAK and use that, it be hard to get in trouble with one unless you wave it around, pull it out needlessly, or do something stupid. After that something like a old school buck lockback wouldn't be intimidating. If you want something more modern a ka-bar mini dozier or some of the spyderco's would be the next best bet to not draw too much attention as they are practical and don't have a tactical look which I tend to see on the FRN and Zytel handles.
Oh and don't tap your knife if it in your pocket to make sure it is concealed when walking by a cop, teacher, staff, security, etc it's a dead giveaway your carying a knife and draws attention to you. If you carry on like nothing happens your good. If you end up being hassled because your carrying a knife remain calm, cool, polite (very important), and explain with confidence (not arrogance, it goes downhill fast) that you were trying to follow all the rules and these steps "X" you did to try to ensure you followed them and kindly ask what rule you were breaking and how to find out more so it doesn't happen again.
