Your clothing can protect your skin from not only the sun and other weather, but also pepper spray. Choose long pants, long sleeves, and a jacket or shirt with a hood. Layers are good for fluctuating temps, too.
Let three individuals who are not joining you know where you are going, when you are going, and when you plan to be back. Ensure they will answer the phone if you need to call.
Turn off BlueTooth, go into Airplane Mode, and turn off your fingerprint or Face ID feature. If you are using your phone to document the event, do not take any photos of protesters' faces to protect their identity.
There is a good chance you will be separated from your group and any location within the area of the protest may be blocked off. Choose a location far enough away from the protest area to meet up at the end of the night.