Doing diploma in Travel/Tourism @ ABE. How much to expect to earn after diploma in UK? -

Hi, I am 25... hence woke up late to realize that i am a looser. I am now looking for a diploma in Travel, Tourism and Hospitality Management @ ABE (Association of Business Executives). I can stay with mom in UK to save on living expense and also working part time to earn for school fees and some pocket money. My question: How much should I expect to earn after successful diploma from ABE in UK? Please be reasonable so that I have pragmatic expectations. My field will be travel and tourism. I am turned myself into a very hardworking guy and sure to fly in the exams.|::::|think around 35,000-40,000...