yeah, that's great!
i'd like to have 10 shares

to make it correctly:

first step: send the 5 btc to the published address: 1LAGSUn1CA24BAtmDTNNrskFTLgRUjj7kq

second step: sign the message --> my btc-address (not the published address)
text should be my btc-address + 10 shares jupiter/saturn each 0.5 btc = 5 btc + my nickname + signature
so i proove, that i own this address

Edit: is this the way to do it?