Hope here your Tutorial:
Step 1: Open Paint
Step 2: Choose black colour(or other) and write your name like i did
Step 3: Choose red colour(or other) and draw lines under your name like i did :P
Step 4: Choose yellow colour(or other), and draw a sun @ the top
Step 5: Take white colour(or other) and draw a cloud @ the top...
Step 6: Draw a sheep(or other thing) @ the buttom
Step 7: Draw grass
And last, but not least Step 8!!!!: Draw a hearth(or something else next to your name)
Tadaaaa.. now you got your own pro sig!!
hope this helped ;).