SpaceX is valued at $1.5 trillion He owns 40% which implies $600 billion in value. His net worth now is estimated at between $735 and $840 billion so this would take him well north of $1 trillion.
You too can get there. All you have to do is start a tech company and sell it for $22 million. Then be one of the group that started Paypal making him $180 million. Then invest $6.35 million to buy Tesla which is now worth between $170 and $200 billion. Simultaneously start SpaceX and continue to invest $1.4 billion in SpaceX. Along the way make another $3 billion in the Boring Company he started, Make a few more billion $ in Neuralink which he started. Also, make several billion $ more in crypto.
That's all.