If you are going to start trading stocks and want to do it from the comfort of your computer you can use an online trading platform to do so. You could also hire a Financial Advisor who has to ability to conduct trades for you. They also give advice on how to allocate the money into investments besides stocks and usually take a 1%+ fee.
My picks for platforms are based on experience and what I have heard from other people.
When I was getting my MBA I had fellow students and a professor recommend this platform as the best overall experience. It costs about $6.95 per trade, which is a little more expensive, but provides you with education and references to help you make decisions and track your investments. Right now they are offering that you can trade free for 90 days and get up to $600 cash. One of the coolest features is the Social Stream so you can see what people are writing on Social Media about the stocks you choose. Combine that with the many tools to analyze your picks and you will be set!
I currently have a Charles Schwab account and I hold one whole stock in it. I used to have more stock in this account but liquidated it to pay for graduate school. Fun. This platform is a little cheaper, around $4.95 per trade. As well, I can speak from experience that they have great customer service. They may have a few less tools to analyze your picks but are a trustworthy platform to get started with.
I currently hold my 401k assets in a Fidelity account. I can tell you that it is easy to use and they have retirement funds you can easily invest in. They are also currently offering 500 free trades when you register and fund an account and usually each trade is around $4.95 per trade. Along with the other platforms they have real time analytics that will help you track your stock picks.
These are the platforms that I have experience with or personal reviews on. However, there are many other platforms to use including E*Trade, Trade Station, Options House, Merrill Edge. Make sure you do your own research and find one that you are comfortable with!