In CSS, we can select an element with a specific ID by using the ID selector, which is defined with a hash (#).

Here are the steps:

1. First, identify the ID of the element you want to select. The ID is defined in the HTML. For example, if you have an element like this: <div id="myElement">, the ID is "myElement".

2. In your CSS, you can select this element by starting with a hash (#) followed by the ID of the element. Using the above example, you would select the element like this: #myElement.

3. After selecting the element, you can apply any styles you want. For example, if you want to change the background color to red, you would do this:

#myElement {
    background-color: red;
}

This will select the element with the ID "myElement" and change its background color to red.