customize Magento invoice

Hi, i need to customize the Magento default invoice that is sent to every customer that makes a purchase on my online store. There are some minimal requirements that an invoice has to have to be legal in colombia. the Data that it should include is: Encabezado: (header) Titulo: FACTURA DE VENTA (fixed value) Nombre de la empresa y NIT: (fixed value) Dirección: (fixed value) Telefono: (fixed value) Actividad Económica: (fixed value) I.C.A Actividad ZZZ: (fixed value) IVA Régimen Común: (fixed value) Resolución DIAN No XXXXXXXXXXXXXXXXXXXX de (fecha) Autoriza del N° xxx al N° yyyy ((fixed value) No somos Grandes Contribuyentes (fixed value) lOGO: CASAMENTO (company logo) Datos de la Factura (invoice data) Factura No (invoice number that shoud match the auotorized numbers given by the tax authority, its a letter followed by a consecutive number) Pedido No (number of the order) Fecha (date of the invocie) Moneda : COP (currency this is a fixed value) Medio de pago y condiciones: PAYU - Anticipado (payment method: this is a fixed value) Datos Del Cliente (customer data) Facturado a: Nombre del cliente (customer name) Dirección: (customer billing Adress) Dirección de envío: (customer shipping adress) Teléfono: (customer phone number) Ciudad (customer City) Departamento (customer Country region) Productos (product detail) Tarjeta de Regalo: (mismo numero de la orden) (product ID whisch must be the same as the order id) Descripción (Tarjeta Regalo + nombre del producto) (product description) Código (Product Sku) Precio (Product Price per unit) Cantidad (Q) (product quantity) IVA (=0) (VAT= is always 0) Subtotal (pre total) Consolidado (summary) Subtotal (pre total) Descuentos (discounts) IVA (VAT) Gastos de Manejo y Envío (shipping and handeling costs) Total (total value of the order) Footer: Recibida y Aceptada: (fixed text) Nombre______________________________________ Cédula_______________________________________ Fecha recibido__________________________________ A visual model of the invoice will be provided, we require the invoice development files ready to be uploaded to the magento system via FTP