One of the problems with any new job is they almost never pay at the beginning what you want, so you can either keep applying, or you can commit to earning your way upwards. Outside of being a member of the royal family, there are very few jobs that pay a good salary from day one that doesn’t change much.
The first step is to double your salary within five years is to do your research. Some companies have excellent pay scales, and other ones have terrible pay scales. For example Pret a Manger the posh sandwich chain pays reasonably poorly when you start on minimum wage, but if you work hard, you can become a general manager reasonably quickly within a year. Thus trebling your salary, but if you don’t become a general manager or an assistant manager pay increase can be slow. An excellent place to do your research is on sites like Glassdoor.com or Indeed.com
The second step is to increase your value as an employee, and that means training. Most jobs have some internal training scheme or even better a requirement for a certain number of employees to have a specific qualification. When working in the IT industry if you study hard in your spare time, you can quickly move up into roles requiring skill in specialist knowledge. If working in management or personnel, you may find some qualifications such as the CIPD (Chartered Institute of Professional Development) can be gained in a year. In fact, a lot of useful professional qualifications can be obtained post graduate in under a year. Look at qualification as being an investment in yourself both of time and money (especially if you end up having to get a career development loan.)
Thirdly is again do even more research, talk to people working for employers you’re considering. Amazon, for example, pays reasonably well for entry level warehouse work but has relatively small numbers of actual managers or specialists on more specialised roles. So expect to start on a reasonable wage and then stay there. Many jobs in the gig economy expect you to be an independent contractor (e.g. running your own private business). This is terrible for any chance of promotion, as you may work for that employer for a decade but as far as they’re concerned you’re little more than the person who delivers pizza.
Make yourself a worthwhile investment; you wouldn’t pay double for the same sandwich you buy at the bakery on Tuesday as opposed to Monday? Well with salaries your employer isn’t going to pay double for you after years if you're still doing the same job. Increase your value to your employer, take on extra responsibilities, take on additional training and check out if your employer has a mentoring scheme where you spend time working and learning with more senior staff. Don’t do this at the expense of your ability to do your job. But you have to think that no pay scale in any post is going to give you double the salary after five years time, in real terms with inflation you’ll probably be earning less. What you will need is to be doing a different job, possibly with a new job title or maybe just new responsibilities.
The main things to remember if you want to double your salary in five years is to; first of all, do your, research, secondly, make a plan. Then thirdly gets as much experience and qualification as you can while on the job and finally don’t stop doing the job you’re employed to do as reliably and enthusiastically as possible.