Leader reads:

This is "rachtzah", or "handwashing with a blessing". Traditionally, we don't use soap, but you might still want to. When you wash your hands, you can say the prayer below to yourself.

When I say "go", you will go wash your hands. OK... go!

Everyone says the prayer below to themselves after washing their hands.

Blessed are You, Lord our God, King of the universe, who has sanctified us with Your commandments, and commanded us concerning the washing of the hands.

baruch atah adonai eloheynu melech ha'olam asher kid'shanu b'mitzvotav v'tzevanu al n'tilat yadayim

בָּרוּךְ אַתָּה אַדֹנָי אֱלֹהֵינוּ מֶלֶךְ הָעוֹלָם אֲשֶׁר קִדְּשָׁנוּ בְּמִצְוֹתָיו וְצִוָּנוּ עַל נְטִילַת יָדַיִם

Wait for everyone to wash their hands and return.

Source: myjewishlearning.org, "Hand Washing"

haggadah Section: Rachtzah