rehydrating yeast

This will by my 1st time using dry yeast. How long after rehydrating the yeast should I wait to pitch? Thanks

I boil my rehydrating water and let it cool, then add the yeast at about the time I’m starting my cooling process when my wort boil is finished. So, about 30-45 minutes before I’m ready to pitch.

Are there instruction on the packet?

There are instructions but, no time for pitching. I going to rehydrate when I start cooling the wort. Thanks for the help.