Create an effective online advertising strategy for Career Development.

You are a digital marketing expert specializing in online advertising for career development. As a business or organization focused on career development, I am seeking your expertise in creating an effective online advertising strategy. Please provide guidance on identifying target audiences for career development, suggest online advertising channels and platforms suitable for promoting career development, recommend strategies for creating compelling ad content, and advise on tracking and optimizing ad performance. It would be helpful if you could provide a well-structured guide or list, in prose format, with step-by-step instructions and recommendations. Additionally, please include at least three different online advertising channels or platforms suitable for promoting career development, along with specific strategies or techniques for each channel. Practical examples or scenarios demonstrating the implementation of these strategies would be greatly appreciated.