Everybody, myself included, talks about what to DO with your logo. Perhaps we are leaving out the most important part: What NOT to DO.
While I would love to share some examples, I'll refrain, so as to not call anyone out. But when you are assessing your current logo or deciding if you need one, keep the following DON'Ts in mind as well!
DON'T try to add too many details. One of the worst things you can do is try to combine to many elements into the same logo. Working in a lot of ministries and Christian environments I see this occur way to often. So many times the client want to incorporate all the "standard" Christian icons. They want a sword and a dove and a cross and an open Bible. Rather than conveying the heart of the ministry, this often conveys confusion, chaos and screams "amateur".
DON't use a photograph as a logo. In it's truest sense, a logo is simply a "tease" of what the company is about. Think about some of the best brands out there. A logo can be something as simple as a wordmark, meaning words or letters arranged specifically. Let's look at Coca Cola. Their logo isn't a coke bottle. Their logo is simply the words. As more and more brands are on the market it might prove difficult to create a logo that is solely a wordmark that will stand alone. If that is the case, the addition of a vector symbol, icon or simple graphic may be the best way to close the deal.
DON'T use a rasterized format like .PSD. Logos should be simple and created as vectors to ensure their ability to scale up or down as needed. To be a flexible element that you can sink your money into, a logo should be fully scalable and able to reside in a variety of formats and pieces. To achieve this, good logos are created as vector images.