double checking lock down date

[veggiecanner]

First time so I want to make sure I am doing this right.
I Set the Incubator May 17th at 12:00 noon. Assorted cross breed layering chicken eggs.
I have it as lock down being ON June 6th.
do I have this right? When do I start bring up the Humidity and how hiigh?
I didn't Know 21 days could be so long.
Can I use t-shirt material to line the incubator so their feet don't fall through the egg grid. We don't buy paper towels. I do have some nonskid shelf liner, would that be better.
I have some tubing and a large syringe ready inc case I need to put extra water in with out opening the incubator. any thing else I might need that I can collect before hand or that I might need for incubating any way.
I have my brooder set up, Is that counting my chickens before they hatch?
Thank you for you help.

 

[sumi]

If you set the eggs on the 17th, your lockdown date is the 4th, hatch is due the 7th (day 21). Up the humidity to around 65%-70%. You can use t-shirt material to line the bottom, but make sure it doesn't mess with your humidity and air flow. Good luck with your hatch!

 

[veggiecanner]

Thank you.