how to make it easy for one group of vba code to use in sheet 1 to sheet 30

dear sir

how to make it easy, that is for sheet 1 , sheet 2 to sheet 100
use the same vba code, now we only can do like follow
how to use like sheet i , for i =1 to 100 ...like this ..
how the vba code will be? pls help

sub easy()

Sheets("Sheet1").Select
vba code

"
"

Sheets("Sheet100").Select
vba code

end sub

thanks
tom

Thanks sixthsense. It work.