There will be protests but I'm not sure if they are doing it in the UK. Just checked http://millionsmissing.meaction.net/ and they are yet to announce the venues for 2018 protests. MEAction Network UK on Facebook last posted something 2nd October last year, hopefully they are just missing a social media volunteer, otherwise it might not be looking too good.
I think that they comprise a group of people who are pretty ill! Goes with the territory I guess.
@Joh's post gives a good range of ideas from the US, and bunting sounds good. I also think that laminated pages pegged to a line are effective. It's a page with a person's picture and name and a summary of their story or what they want to emphasise.
Shoes are bulky to transport and last year they were delayed in heavy traffic on their way to the Dept of Health. I was also delayed by Southern Railways, though that was less important.
I'm glad I got some mad bright red and blue (separate packs) hair extensions, from a shop in London recently when visiting friends. Maybe Blue for the IiME conference, instead of my Marge Simpson blue wig and red for #Millions Missing.