Fitness advice, what am I doing wrong?

I have recently been tempted to start taking steroids as despite a regular work out routine my body still looks sh**!!! I have been going to the gym now for 3 months for 4 days per wk on average and despite being able to lift weights, run, row and swim with the best of ’em my body has changed very little. My friend is the same size as me but despite being on the same fitness level as me I can see him becoming better shaped. Any ideas, does anyone know a great fitness routine or should I go with the steroids which I have been warned about taking.