you will use this for means of signing a message with an address you own
wallet that you control
-----BEGIN BITCOIN SIGNED MESSAGE-----
This is a29645 from bitcointalk.org today is (today's date), this is for proof of ownership of the address
-----BEGIN BITCOIN SIGNATURE-----
(your address)
(signature)
-----END BITCOIN SIGNATURE-----
here is mine
-----BEGIN BITCOIN SIGNED MESSAGE-----
i am jjrundy from bitcointalk and this is my address, today is 8/9/2017
-----BEGIN BITCOIN SIGNATURE-----
1MuW8PRqs39b7Uye8SZUpv55QFZe8h6Y2U
ILekmoSiZ0Iv2Wwm8ec34Q+UpyeBiuYnvQR6wTNs5vXiSXxK78p3AqI5dC2431ki3rc26wxgARIEnrb3BbAV+CU=
-----END BITCOIN SIGNATURE-----
verify the message here
https://tools.bitcoin.com/verify-message/, and also it needs to be an address previously published in an old thread here.
p.s. i find it absurd that you will put 25k in a mining operation but don't know how to sign a message.