Is doing an action like chalking or flyposting going to get me arrested?

You are highly unlikely to be stopped whilst doing this type of work in th UK.

If you are, it’s more likely to be by people who work in the industry rather than the police. Avoid giving your name or details to any industry worker. You’re only obliged to give your details to the police, and even then, only in certain circumstances.
The situation varies depending on external factors and location, particularly in countries with different laws. Spray-chalking usually provokes the police if they see you do it. There have been incidents of rebels receiving a fixed penalty fine of £90 for chalking outside a company HQ.
In the worst case scenario, a charge is likely to be that ‘criminal damage’, which holds minor penalties.

For more information check out: [Greenand Black Cross website( criminal-damage-theft/)

Note: Avoid taking or posting photos of anyone doing the work as it can be used as evidence in the future.

Police liaison:

To be an XRUK action, some arrestables should stand by the action and face possible arrest. This does not necessarily mean you have to tell police exactly what you’re planning; this is an action individuals or affinity groups (outside lockdown) can take alone, and as such is more easily stopped by police than a mass action. Scout your meeting location an hour or so beforehand to check for police presence.
In the UK (this advice will vary depending where you live) we don’t recommend running away if police find you taking action. This could be classed as resisting arrest and may also make them think you’re doing something far worse than you are. However, some members of affinity groups could calmly and quickly walk away, or even continue the action, while the police liaison negotiates with them.
Know Your Rights online training takes place every fortnight, you can sign up on the facebook page here.