I want to get into a costume for my SO.. what outfit? and how would I go about this? like how to start it off? I'm pretty shy lol.
Classics like school girl, cheerleader, nurse and teacher. Oh you could do secretary. Cop....Anything!
I can say dress as a french maid and wear this, 
Make your husband leave off somewhere or plan this when he's out at work or the store! When he comes home let him find you wearing this and bending over ironing and also feathering/dusting the house! Dont break your role and stay in character no matter how surprised he is. Don't let him touch just yet let him enjoy a show of a maid with a very short skirt who is bending and stretching to clean every nook and cranny in the house. Once your finished tell him your master is out and he must pay you now in some way...
Be an office secretary!! While he's watching t.v./video games or whatever he does that requires sitting down come dressed in a secretary outfit!! 
holding a pen and notepad ask him something work related as if he were your boss. Say sir, about the johnsons documents, where should they be stored?? and let it play from there.
Thats all im gonna give you lol i would be giving too much away that i have already dedicated to our group members :) Join the group SS and we CONSTANTLY give tips advice on everything from role-play to blow jobs, lap dances/chair/pole, and so much more!! Good luck!!
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