Getting back into Fitness!

Hi everyone, so I am just getting back into my fitness after having such a long time off. I'm finding it really difficult and although I am not out of shape as such I do feel more sluggish and carrying a few extra pounds lately. I really need some motivation to help me get back into it! I find it quite difficult as I work 8am-4pm Monday-Friday and by the time I get home i'm too tired and hungry to do anything. What do you find works best for you and what motivates you to stay on track with working out?