Anyone who learned it name his favourite exercises to learn it step by step

Explanation: got robbed and slapped in my face yesterday (only 20€ stolen but still a robbery) and it brought me to realise that life can be short so you should live in freedom, now i don't want to sound cool and yeah i'm scared as shi right now about when and if those robbers will find me again, but i know that this negative moment in my life will give me a chance to rebuild myself stronger than ever. To whom actually readed this completely I thank you for your time and may god support you through your own life journey, AMEN🙏

As the title says: when i try to do a good form l sit the 2 thin muscles in my popliteal flex and i cant get my leg in a perfect L form, how would i combat this?