As Mandville has stated...... "accredited by who?"
I would not add accreditations to your site unless you have the paperwork and certification to back it up....
Reference how much money can you earn.... "How long is a piece of string?
Everything that has been stated is very good, but there are 1000's of websites out there that can help, guide and define you as a person with who and how you want to move into the web development and web design business and make money.
But, it is not an instant hit.... I have for example taken a year to get my business to where I want it to be, everything takes time, patience and above all "belief"
in your ability to earn the trust of your customers to build long term business relationships.
The others have stated that having clients is a good start, this is indeed true, but you also need to have the energy
to go out and get these clients in the first place, and as stated you need a website to attract people to your site and its a good idea to also do some market research.
I went to three of my local towns in Brighton, Hove and Hurstpierpoint and went into the businesses and spoke to people to ask if they had websites and would they use a local company if they were very good at what they did.
The response I received was very good and due to this market research I now have 45 clients in the last 12 months of trading.
I already have 18 clients this year so far, but that has been from pounding the phones 4 days a week and making 50+ phone calls a day and going out to see clients face to face to sell the services of website development,marketing services ETC.
Making money is good, but it is not easy to make fast money unless you win lottery or everyone would be web design millionaires
I seem to have warbled a bit, I wish you well and good luck.