If you want a really simple way to boost a hashtag on Mastodon then there is a really simple way to do it! Just search for the hashtag on hashtag.place like this @hashtag ie. @3dcsocial and then follow the account that pops up. Every few minutes there will start to appear boost with that hashtag. I have created a few and it works very well!
So for this post it should be tagged with the following hashtags #3dcandy #3dcsocial #socialmedia