When you begin making a website, you want to make sure that the initial design of the website fits with the information and products that you are putting on it. Too often there is a dichotomy between what the person conveys through the design of their website and what they are actually putting on it. That can all be fixed if you take the time to design it right.
Font is a big part of the appearance of your site. When you pick a good font, then your information automatically looks more credible. While it should not necessarily be so based on appearances, that is the way that things go and you just need to make sure that you roll with the way it works. If you have a serious business site, you do not want to pick some quirky and handwriting kind of font. You want something classic like Times New Roman. That indicates that you are serious about what you are writing about and presenting.
Having a good background and color scheme can help. If you have a quirky site then you do not want to have an all black set up with a dull background. Likewise, if you have a serious site then you do not want turquoises and yellows popping up everywhere. If you do not even take yourself seriously, then you cannot expect anyone else to.
Keep everything coherant because that is what will make your site look professional. If there is a gap between presentation and content then you have a problem.