Hola Tanner como estas, te contare mi experiencia con el alemán y el ingles, te recomiendo aprender palabras sencillas, unas 3 a 5 por día, con su pronombre, y como se escribe en plural, de esa forma ampliarás tu léxico, después comienza con el verbo, ser, estar y haber como te dijeron en la otra pregunta, y ten cuidado con las películas o grabaciones que ves, por que puede confundirte un español de un país, con otro, saludos, agregame si tienes mas dudas, no cobro =D jajaja

Hello, Tanner: This link will provide the best free resources to start learning Spanish from levels A1, A2 to more advanced levels B1 and B2. Please, check them out because it has everything you need to start learning Spanish: http://eoilacorunaenespanol.blogspot.com.es/2011/10/espanol-para-principiantes.html I sincerely hope this helps. All the best!

I think the next step depends on what you want to speak with your customers, that makes you choose the vocabulary. But you need the grammar as a basis so I recommend you start before of all with the difference of ser and estar, in English is only one verb: to be. The conjugation of verbs is the most difficult I think in Spanish so it's good that you start with these used verbs, start with present. To sum up, choose the vocabulary and go to grammar, principally conjugating verbs such as: ser, estar, haber, ir,...

Get a course and start learning, like Teach Yourself or Colloquial. Learn vocabulary that is related to your job on top of the course material.

I think that you need to learn vocabulary related with your job i mean if your costumers speak spanish it would be good that you study the expressions that they use when they ask you something or how do they ask some stuff that they need and for the vocabulary i recommend you search a dictionary in the website english-spanish and start searching meanings hope this help