Go onto non-Labour Party Facebook groups and pages and get involved – comment on posts, challenge. Like the comments you agree with, challenge the ones you don't.
Get a group of people together – the more the better - and draw up a list of sites - FB, local blogspots, anti-Brexit, etc you want to invade! Draw up a rota to go on the sites everyday. Post if you can and/or comment if you can't. Tag your group members when you comment so that they can join you, like your posts, and join the debate.
See what it is that bothers the other contributors, and start from where they're at. Make sure you stick to the site rules so you don't get deleted or thrown off! Most importantly know when to stop – if your words are getting nowhere don't get drawn in, and try again another day. If you come across someone who agrees with you consider messaging them – you might convince them to join the LP or even join your pack!
Arm yourself with the arguments - try https://fullfact.org/ - they are running a special general election section at the moment. Use the resources on: https://www.facebook.com/groups/LabourInternationalVictoryin2017/ page.
Make sure your list of pages/groups include non LP sites:
- Conservative Party - https://www.facebook.com/conservatives . Possible to comment and there are already several anti-Tory comments there! Join the guerrilla campaigners on there and get the LP heard! You don't have to join the group!
- Liberal Democrats - https://www.facebook.com/libdems . Also possible to comment without joining.