Making them feel silly is infinitely better than getting mad, trying to debate rationally, or engage on relevant issues.
Anti-anti-protest signs are the great, as is clever retorts like having a clown wig and nose in your bag and standing next to them with a "clowns for fascism" sign
If you are unprepared for counter protests, the next best thing you can do is ignore them and drown them out. Let them be there but let their numbers show.
Things like loud instruments, if you have speakers, playing "baby shark" on full blast, etc. while otherwise ignoring them can easily work.
Remember at all times they are here to get you to engage with them directly. Don't give them what they want.