How to repent from major sins

Assalamu'alaikum how to repent from a major sin you knowingly committed... Jazak Allah khairun

Alaikumassalam wa rahmatullah,

If the sin doesn’t involve the rights of other people then all you need to do is repent and you will be forgiven inshaAllah. But if it involves the rights of others, as in stealing, then it is necessary to repent and return the stolen thing.