Theres this girl that i was in the school production with.. its a pretty big thing in our school/6th form (rehearsals and so time of first socialising with her started in september and the play ended November 5th) .. anyway I was the lead guy and she was the lead girl hence us kissing in the play..
On the first night i went for a single kiss.. as i had in all the rehearsals..
on night 2 and 3 i gave her the initial kiss and then leant back in after kinda leaning out for a second plant of the lips yano.. and she responded well enough

and we spent a bit of time chatting but not much.. and basically im in year 13 (upper 6th form) shes in year 12 (lower 6th form).. and we have lessons at different times so when i have free periods she never does and shes never in the common room at lunch.. so basically theres no time to socialise..
i need advice on what to do now..

What do i do and say when she actually is in there occasionally and how do i build her attraction for me? i mean i know neg, cocky funny, DHV and qualify but this situation seems unfitting because shes not there and i need a bit of time for all this sh*t..

im trying to get her on the weekends but shes alwayys busy..
anyway this weekend we're both going to the same party.. now im practically 100% sure shes single.. but she is going with a mate she hasnt seen for ages from up north.. anyway, what i wanna know is what steps do i take from here, how and where/when do i build attraction and what do i do at the party? i dont want to follow her round like a lost sheep but i dont wanna not talk to her the whole party.. i wanna actually get somewhere..

so can you gimme some advice please?!! ive got other girls as options but i like this one the most and so would like to go somewhere with this..