Markus,
If I was advising someone who needed a job (and I appreciate this possibly doesn't apply to you) I'd suggest they talked to as many people they could that had already found and kept a job - and found out how they did it and any advice they might have.
I'd then ask then to consider what their potential employer actually wanted and what they themselves offered.
And take some action based on the results.
Only when they had done the above might I suggest they learnt about language patterns, but more more as icing on the cake and their own development - and they probably won't need it as by then they would have probably found a job.
I do know people who could walk into a job using language patterns, but they've practiced for many, many years.
Interested in other views.
(And as mentioned elsewhere Jamie Salad has some
great cards for learning about language patterns)