There are hundreds, probably even thousands of different natural sleep aids available, marketed as being safe and genuine. The problem with these is that they are unregulated by the FDA (US Food and Drug Administration) and we can never be sure whether they will do us more harm than good. Luckily, we can implement routine into our lives as a way of inducing sleep, without ever needing to swallow or smell any particular herbal substances.
One natural sleep aid to consider should be improving sleep hygiene. This doesn't mean washing your bedsheets once and months and wearing clean pajamas (although this might help a little), but rather that you regulate the time that you go to bed, make sure you don't have a television on in the bedroom, a laptop running or pets coming in and out to disturb you. Sleep hygiene incorporates things like never working in your bedroom as you'll be in a working state of mind as you try and sleep. Also, try to have a constant supply of fresh air and remove any allergens. Quite simply your bedroom should be associated with sleep, comfort and sex if you are active, but never work or anything stressful as this will keep you awake. Routine is a vital part of sleep hygiene too, as small cues that it's 'time for bed' trick your brain into producing melatonin; the hormone that induces sleep. One of the best things to do here is have a warm bath, followed by a mug of warm milk or hot chocolate whilst reading a book. Baths cause our core temperature to rise, but then drop dramatically about an hour after getting out, to the temperature that makes us feel sleepy. Warm milky drinks then also make us feel calm and tired, whilst reading a book takes our mind off daily stresses. It makes sense in this way that you should avoid activities you normally do as part of your morning routine, such as having a shower, walking the dog or drinking coffee.
While exercise is generally frowned upon right before bed as it wakes you up, sex is a far better option that will keep you fit and help you get a good night's sleep. Clinical studies have proven that when both men and women orgasm, their brains produce endorphins (hormones) which make you both happy and sleepy. The effects of these hormones may be very temporary, but they're often strong enough to induce sleep quite quickly so that the 'waiting to fall asleep' period is considerably shorter.
If you are living without routine then it makes sense that your body never knows when it should be sleeping. Humans are built to sleep best when it is dark and be most active when it's light, with one short period of sleepiness during the day (the circadian dip, at around 2 pm, lasting around 40 minutes). For this reason it's a good idea to follow this pattern, but if you have problems sleeping at night try not to nap during the day. If you still experience insomnia then you should visit your doctor for further advice.