AW feedback can only happen following an actual booking through AW. Phone calls, text messages etc won't create a feedback opportunity.
Even then the lady has to confirm the booking. Then you can leave feedback for them. And also they can leave feedback on you.
In practice, to start off generating feedback ON YOU, you will need to make the booking with a lady that does not mind someone with no feedback.
Then you must go through with the meeting and behave yourself.
It's OK, in my experience, to then ask the lady to leave feedback on you. Mostly they will unless you were objectionable somehow.
Helps to book with a well reviewed UK lady of some standing. Avoids struggling with language.