Watch Black Belt Barrister on YT he is very accurate and explains the law clearly. He also has a number of videos worth watching.
Not to sound righteous in any way, but as a community we have a responsibility to know the law, respect it and be ambassadors for safe sharp tool use and ownership, because we are only one or two d**ckheads away from changing the laws.
First thing is knowing the difference between legal carry and justified use. Any "non-locking" folding blade under 3 inch is legal to carry without justification, think slip joints like Swiss army knife. Any fixed blade any size is NOT legal to carry without reasonable justification, incumbent on you to demonstrate. E.G a carpet fitter has a Stanley blade and is stopped in his van between jobs, justifiable. Same carpet fitter walks into Tesco with the blade and now he is outside the law. "I forgot it was in my pocket your honour" is not a reasonable excuse, however this also brings me onto the last but very very important point, your behaviour, appearance and general demeanor. If you draw attention to yourself, behave in an arrogant cocky or aggressive way you can bet you're getting locked up!! If you decide to bushcraft in a park near families and city folk you are risking it too. Finally, you should always be able to demonstrate that you tools are safely packed away and out of site.
Apologies for the lengthy post that might seem highly obvious to some. A lot of this is subjective and to protect yourself from falling on the wrong side of the law it is worth having the right mindset and taking a sensible approach. Knowledge is power.
Last thing. Most cops will apply the attitude test from the minute they interact with you. It's not hard to be calm and reasonable, even if you're uncomfortable with the boys in blue! Hope this helps anybody out.