How make faster my script

[RicardoNones]

#include <AutoItConstants.au3>

Local $i = 0
Do

Opt("MouseClickDelay",10)
MouseClick ( "left",760,657,1,0)

Opt("MouseClickDelay", 10)
MouseClick ( "left",757,232,1,0)
$i = $i + 1
Until $i = 1500

[water]

Welcome to AutoIt and the forum!

You do not need to set "MouseClickDelay" over and over ... The option stays in effect until you change it. So move the Opt statement to the top of your script.

BTW: Which program do you try to automate? MouseClick is not very reliable as it depends on screen size and resolution, window position etc.
Most of the time there are more reliable ways to do what you want to do.