How do I change my name away from guest_weird number

22/09/15 23:29
How I change my name here away from guest_weird number? I really would like to change it quite badly.
23/09/15 11:31
Done.
23/09/15 13:07
Thx
23/09/15 13:07
Thx
27/09/15 02:16
How do I change mine?