1. Prepare to protest safely
Whether organizing or attending a protest, don't do it by yourself. If possible, bring a buddy or accompany friends. Wear comfortable shoes and clothes, and avoid bringing a bag of any kind. Keep your ID and $20 cash in your pockets, along with a handkerchief or paper towel. Bring any medicines you might need (and a photocopy of your prescription if you need one). Do not wear jewelry or bring any valuables other than your cell phone.
Speaking of your phone, disable the fingerprint-scanning security feature, which police can compel you to use, and instead enter a passcode that you can "forget" if your phone is seized. Sign out of your messaging apps and social media accounts. Keep your camera app on your home screen, so you can quickly take video.
If you're outdoors in the daytime, wear sunblock but rethink bringing a big water bottle with you. There might not be restrooms and you may want to keep your hands free. If you need to bring water, bring a disposable paper or (shudder) plastic bottle, not glass or something you want to keep.
2. Understand your rights with police
Nearly all organized protests have a police presence. Though most people don't attend protests with the intention of getting arrested, it can still happen, even to bystanders and journalists.
Assuming you are not trying to get arrested, always follow police instructions on where to walk or stand. Protesting is allowed on most public property, but remaining on private property or in a designated no-protest zone can lead to handcuffs.
If a police officer asks you to identify yourself, give your full name or they can arrest you. Florida is a "stop and identify" state. If you are stopped or questioned, ask if you're free to go. If the answer is yes, walk away calmly and without responding.
Don't lie to the police or tell them anything you don't have to. If organizers have planned for members to be arrested, encourage them to have a plan with bail money and an attorney at the ready.
3. Build relationships to stay in the loop
Sign in to the protest with organizers and share contact info with other attendees. Find each other on Facebook and exchange cell numbers. Invite each other to events and organizers' websites.
Sign up to follow the organizations in this guide on social media, and accurately indicate whether you'll be attending, in order to better help organizers prepare.
Offer to volunteer and help with future actions and protests, rather than starting your own.
4. Keep growing and keep showing up
Learn why others are there with you. If you are not Muslim, black, transgender or otherwise a member of a vulnerable group, learn about the issues and policies affecting minorities, and how to be an effective ally.
Join political campaigns, volunteering whenever possible, using the skills you are best at providing. Most candidates need a treasurer to keep track of the finances and reports. They need people who will bring them to their workplace and introduce them to the people who work there. They need sign makers and chant-starters. Seek out a campaign that is organized and able to win, but don't expect volunteer opportunities to always be listed on their website. Offer your particular abilities, but be willing to help where needed.
Avoid running for office until you have already volunteered on an organized campaign. This is the single best way to learn the basics, and it will lead you to other resources to learn about running.
Learn the history of other resistance movements. Read up about non-violent direct action and civil disobedience from the ACLU and other organizations. There is comfort and clarity in recognizing cultural patterns, and it can help you find the best role for you. – DP