Step 1: Find an image host that allows editing of your pics.
Step 2: Deploy some libtard.jpg bait meme links. Spread them far and wide, upvote, make it viral.
Step 3: Edit libtard.jpg to shitpost.jpg
Step 4: (optional) Switch them back and forth to create confusion.
Step 5: Collect salt as libtards turn on each other.