To write the general form of a conic section with given foci and a y-intercept, the first step is to identify the type of conic section involved, such as a parabola, ellipse, or hyperbola. Understanding the specific formulas for each conic type is crucial, as they dictate the approach to take. Foci are always located within the vertices of the conic, which is an important consideration in the formulation. Once the correct equation is determined based on the conic type, the next steps can be taken to derive the general form. Proper identification and understanding of the conic section are essential for accurate representation.