Fangirling comes in stages. First, you watch an episode, movie, or listen to a song and then it clicks. You instantly want to get to know the actor or singer immediately. When I watched "Jurassic World" I saw Nick Robinson and had an instant crush on him. I went home and binged watch "Melissa and Joey."
The second stage is what I call the rabbit hole because now that you gained the admiration for the person, you want to see what they act like and every little fact about them. You go on YouTube and type their name and watch every interview they have and find videos of them. If they are a band you watch music videos, interviews, and red carpets. Even now I still watch One Direction music videos, interviews, and their documentary "This is Us" because I am still a huge fan. More recently I discovered Chase Atlantic and binged all their music videos and interviews.
The third stage is social media stalking consisting of Twitter and Instagram. Follow all the members of the band or follow the actor on social media. Literally, like all their pictures and leave a comment as soon as they drop a picture or tweet. DM them and see if they respond, they probably won't, but it's the hope that keeps you going. Make your love for them known!
The fourth stage is joining the fandom. I promise you WILL NOT regret it. The fandom is a beautiful community that keeps you updated on your favorite celeb. They have all the info on them like who they are dating or potentially dating. They can also see if they have an interest in someone by checking to see if they liked other celebs or individuals outside of the spotlight's pictures/tweets. The fandom has all the knowledge like news of the celeb releasing new music, or getting a new part in a movie. There is a dark side to the fandom like the trolls who bully the significant others of the celeb, or even troll the artist they are fangirling over.
The fifth stage is wanting to meet the artist. I still hope I get to meet Shawn Mendes, Nick Robinson, members of One Direction, and Chase Atlantic. You enter contests or do a little social media stalking to see if they are in your area (that is if you are in the same city as them).
Finally, you support them through everything because you genuinely love them and want them to be successful.