First time dosing

hey guys

i got my hands in some purple mickey mouse, advertised with 20mg 2cb i've tested them with the mandelin and marques reagent and both are positiv on 2cb we plan to take them on saturday but we are unsure which dose we shoud do for our first time. we are both experienced in weed, mdma and LSD (max about 120µg). your plan was to draw a little, talke a walk or watch planet earth 2, so we have full controll over your setting

So question one: what is a good starter dose? and the second question: What would be a party-dose? i've heard smaler doses are more like MDMA and biger doses are more like LSD. but where is the line?

thanks