One of the hardest parts of starting freelance work is building a strong portfolio to attract clients. Your portfolio is your biggest advertisement—it is what will make you gain or lose clients. It is one of the most important things for a freelancer. Firstly, build up your portfolio before fully committing to freelance—if possible. In order to get clients, you will need to advertise your services, and you need content to do so (so make sure you have some)! The biggest mistake freelancers make is to start freelancing before they have a freelancer portfolio.