Hey there! In simpler terms, marginal costing focuses on the incremental or additional cost incurred while producing one additional unit of a product. It is helpful in determining the break-even point and making decisions related to accepting or rejecting special orders. Let me know if you need any further clarification!

I agree with l1l. Waxing and threading are must-haves. Also keep the parlour clean, hygienic and welcoming. Provide good service and quality products. Build a loyal customer base through good word of mouth. Best of luck!