You have not chosen the easiest starter heels!
There are a lot of good visual guides on YouTube, so I would suggest watching them. Search, “How to walk in heels”, or something similar as it’s much easier to watch and copy than to describe.
To be honest, I would also suggest starting with 2.5"/3" kitten heels rather than 6" stilettos so as not to break your ankle before you learn the technique!
There is nothing sexier than a confident, balanced walk in killer stilettos but this takes time and practise to perfect and you’re not going to master it overnight. Bambi on ice doesn’t scream sexy.
This thread How to walk in heels has a few tips in to get you started 
.