It is recommended that you get to your workout routine a minimum of three days a week, and 30 minutes each time. One should be shooting for a relatively high intensity workout, say about 70% of your maximum heart rate (determined based on age, gender, and other factors.) It is vital that you train in the correct intermediate zone. If you aren't working hard enough, or conversely are training too hard you will not see significant results and may risk injury.
Remember that consistency is key, you need to stick with your program. It can take up to two weeks for your body to start adjusting to that new routine, and two months before you've fully adapted to your routine. This means take it slow, be consistent, and push hard when you feel your body can handle it. Don't expect crazy gains in performance immediately, but work towards them. Put your goals on paper and go achieve them!
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