how can i bet to a odd off 2

people i wanted to know in poker x'hold em how can i bet at odd 2 when the odd in real is up than 2. imagine:

hand 1 in favour is 3.2 and i want to put at odd 2, in order to enter only if he decreases.

thanks.

You can place bet when the price is 2:
Action: back/lay
Conditions: Any selection's back price is equal or lee than 2