Your personal blog? On the forum? 
There won’t be any issue if you’re not making money from it. If it’s relating to a business I think it’s OK to post once and then only if someone is asking (ie if someone asked, “does anyone make Y” and you do, or if someone is asking for gift suggestions, or who has a shop, etc).
If it’s a personal blog, I don’t think there are guidelines. It would be fine to share if you posted something we might be interested in.
Some folks share their link fairly often, some don’t ever promote themselves for any reason and leave their link in their signature only.
It’s a personal thing, and also depends mainly on the purpose of your blog.