Here's what I should have done for Product Hunt :)
You have to use something colorful and visible for the thumbnail. Especially for those using the chrome extension. Something like a red border.
You have to set up the text replacements (shortcuts) on mac, so you don't waste time when you message people for an upvote.
I had made a list of 100 people but to get to the top 5, you have to work with lists of at least 500 people ^^
When we look at the notable upvoters on the dashboard, they have the most followers. So it seems that Product Hunt is looking at that, and suddenly, you have to look in his contacts on Twitter which has a lot of followers as it is often linked.
My LinkedIn post brought me a lot of visibility, which was a good thing https://www.linkedin.com/feed/update/urn:li:activity:6980422712477286400/
To respond to comments quickly on product hunt, you must use the notifications tab rather than constantly refreshing the product page.
Ideally, in your list of people to upvote that we have in Notion, it's great to add a column with a link that directly opens the conversation for D-Day :D
By the way, I'm live on Product Hunt today if you want to upvote me :)