I think it depends largely on your situation, what makes you happy, why you are depressed, a multitude of factors. Just like medications, and therapies, and other forms of depression treatment, no one daily routine is the cure all for everyone with depression. That being said, I can give you some tips on things I've used during daily routines that you can mix and match into yours to see what works for you. Something I've found really helpful is taking time for yourself when you wake up in the morning. Take an extra few minutes, however long you can spare, and just focus on yourself. Identify how you feel, smile even if you don't feel like it (it's proven that smiling when you don't want to will make you feel better anyway even if it's just a bit), do breathing exercises, meditation, browse a funny picture site on your phone. Start self care early, put yourself before anything or anyone else. Second bit of advice would be to EAT BREAKFAST. It really is the most important meal of the day, and eating regularly and healthily will improve your moods. Getting exercise is important as well and it's not about losing weight, or getting buff/toned, or whatever else, it's simply because it's good for you, so making exercise a part of self care can make it more fun. Exercise doesn't have to be grueling, it can be yoga, or just dancing in your room, or a relaxing bike ride. Getting those endorphins pumping everyday or at least every few, though, will help improve your mood. And most importantly for improving your mood, you need to spend time doing things you enjoy, which can be hard sometimes when you have depression because it can sap your love of hobbies and activities you once liked. But if you loved it at one point, try it anyway. If it's something fun and relaxing, take a half hour a day and try it anyway.
I'm also going to just throw in, you need to get out of bed even on days when you don't want to.
Last but not least, make sure you build a good support system. Use websites like this regularly if you find they help you, seek counseling, find support groups in your area. It's important to feel you aren't alone, because otherwise it can be impossible to find the motivation to fight this.