I agree with this guy:
Something unique. Something fun. Tease her. Show some personality. So many guys don't have any you will stand out like a sore thumb in a good way.
Men get like 5-6 matches a week (the first few days you get more matches because your profile is new and Tinder shows it to more women), while women (at least the 6s, 7s, 8s, 9s... 10s don't use Tinder.. even 9s only use to feel good about themselves) will have a match with every guy they swipe to the right. So you need to stand out. If she has a boring evening and starts swiping on Tinder she will easily have 15-20 new matches.
So make sure your opener stands out or she won't even respond.
I usually try to make her laugh and like that dude said, try to show some personality. If there's something in her profile I don't like. I tell her that, but I make sure to add something positive to it aswell. Most men don't dare doing something like that, so you stand out. Just don't act aloof or act like a ****. It's easy for her to delete a match.
Get her to feel something. Show you have a sense of humour but don't be a clown. Nobody wants to bang the clown. But you do want her to think.. who is this guy? Most matches fail to do this.
After that I try to make some report. It shows her you have a serious side aswell. Show some genuine interest in her as a person.
Then some light banter and I also try to create an inside joke (a nickname, something she said you can tease her with, etc). This makes it easier to bond. You can also mention something weird another match has send you.. this reminds her that you are talking to other matches (pre-selection, women want a man other women like) and also makes it possible to talk about how many weird people there are on Tinder. As backinthegame78 said.. most women will agree that the app sucks and in a subtle way this shows her that you aren't one of those weirdo's. Because make no mistake.. most women fear being matched with a creep/weirdo more than anything. It's online. It's easy and everybody has access to it. In real life she can filter out the weird ones, but online she can be fooled by those 3 or 4 pictures. It also gets her to agree with you on something. Work with this and get her to agree on other things aswell. Subconsiously.. if she starts agreeing she will like the conversation more and she will like you more.
Make sure to end the conversation when it's going well. You are a busy man and you don't want to overdo it. It's easy to f**k things up when you keep posting and chatting. And when she ends the conversation because she is sleepy or has stuff to to, in a weird, subconsious way it will feel like you were needy. You wanted more. Don't do that. You decide when the conversation is over and always end it on a high.
Two days later you can send her again. Repeat the same sequence. Make her smile or laugh. Get her to share something about herself and tell her something more about yourself. Mirror her texts. Don't go overboard with smileys and certainly don't use too many smileys if she isn't using any of them. Don't write longer texts than her. Try to match the lenght of her messages, of make them a bit shorter. Again, subconsiously, don't give her the feeling that you are more into her than she is into you.
After that I usually don't contact her again until she sends me first.. this is what you want. If you did it right (and I made a lot of mistakes in the past) she will wonder why you aren't chasing her like all her other matches. She liked the conversation and wants to continue.
It's fairly easy to get her on a date after that.
Personally I don't like Tinder. Because of Corona I installed it again after 3 years, but I prefer meeting women offline. The really hot ones won't swipe me to the right. It's a whole other ball game when you meet these hotties in a different setting. You get to show them who you are, rather than hoping they like your face.