Due to changes in lifestyle anxiety,  stress and depression are quite common now days. 
What is anxiety, stress and depression?  Although these are mental disorders, they differ from each other.  Briefly - 
1. Anxiety arises from fear of loss of material objects or a person.  It is also caused by excessive worrying and negative thinking. 
It symptoms are loss of appetite, moderate sleep disturbance,  palpitation, perspiration tremors and rapid breathing. 
2. Stress arises when one  feels pressurized, struggles to fulfill wishes and desires, inability  to cope with a situation, loss of concentration and accuracy in work,  sleep and appetite are disturbed. 
It symptoms are lethargy,  tremors, sweating, tiredness, weakness.
3. Depression arises when  there exists a feeling of helplessness and loss of hope in life. It  comes after anxiety and stress. It results in us blaming others  without reflecting to see where we are at fault and suicidal  tendencies. We lose interest in any activity, wish to stay alone and  avoid social interaction. When depressed we lose confidence and cry  repeatedly. 
Its symptoms are lack of  sleep and appetite. 
What type of people suffer from  anxiety, stress and depression? 
It could be a whole range  of people. Sportsmen & the general audience spectators  watching the play, women, office goers, students, and different  professionals like doctors, advocates and engineers do experience  these symptoms sometimes in their life. Also people who are  highly active people in their fields mostly suffers from above mental  disorders.
How do these problems affect your work  and family life? 
All of us need to maintain a balance in  what we do and a work-life balance. Failure to do so shall result in  anxiety, stress and depression. Actions taken in such a state of mind  could result in taking wrong decisions which could lead to financial  loss and disturbances in family life. 
Can Yoga help in managing stress? 
Yoga is the best way to  manage such mental health disorders. It's holistic approach helps  eradicate such disorders from the root. This is not to say that  alternative therapies available like Ayurveda, diet, medications and  naturopathy do not work. They have their limitations however. 
Here are a few tips to manage  anxiety/stress/depression.
1. Preparatory steps 
Sit  in lotus pose, or easy crossed legged pose on the floor or in a chair  by keeping spine & neck straight & facial muscle relaxed.  Eyes should be closed. Observe your normal breathe.
Yoga practices 
1. Breath Awareness – 10 -20  cycles 
Closed your eyes with  awareness of eyelashes, eyelids and eyeballs. 
Ensure complete closure  of eyes & relax. 
Then concentrate on  normal breath and watch it as it is going on, for 5 cycles. 
Try to feel the flow &  the touch of air inside the nostrils. 
Feel the coolness of air  while inhaling & warmness of air while exhaling for 5 respiratory  cycles. 
2. Slow &  Conscious Deep Breathing 
After breath awareness,  progress further with conscious. 
Deep inhalation &  exhalation with awareness of movement of Chest & abdominal part.   Try to follow the air entering from the nostril going through the  throat then feel the movement of chest, the way it comes out which is  then followed by the abdominal part which also bulges up. Then watch  consciously the reverse movements of the abdomen & chest going  inside respectively while exhalation. 
Please remember, breathe  very slowly so that there should be no sound from the nostrils during  inhalation and exhalation. 
One breath cycle may take  10 to 15 seconds approximately. (Inhale fully up to the collar bones  and exhales completely)
3. Anulom Vilom - 10 to 20 rounds
This is nadi shuddhi  technique of Hatha-yoga. Commonly it is also known as Anulom- vilom   pranayama though it is not among 8 types of hathayoga pranayamas. By  doing this one feels calm and quiet. It also increases focus. 
How to do? 
Close the right nostril &  inhale deeply from the left nostril. Close the left nostril and  exhale slowly from the right nostril. 
Now inhale from the right  nostril, close it and exhale very slowly from the left nostril. This  is one round of Anulom vilom pranayama. 
Please remember  exhalation should be longer (in time) than the inhalation.            Beginner may observe ratio 1:2 for inhalation and exhalation.
4. Bhramari Pranayama  - 10 to 20 rounds
In this type of pranayama  inhalation is done with both the nostrils. During the   exhalation  humming sound is produced with closed mouth.
5. Omkar recitation -  10 to 20 rounds
Loud but low pitch Omkar  chanting increases peace & strength of mind. 
Because vagus nerve is  connected to vocal cords they get toned up. The  vagus nerve is part of the parasympathetic nervous system.  It is  largely responsible for the mind-body connection & has far  reaching effect for all your major organs of the body.
How  to chant “OM”? 
Inhale  deeply & while exhaling initiate chanting by saying ‘O’ (with  the lips open) and them ‘Ma’ (by closing lips) with full  awareness of body & breath coordination. 
Visualize  & chant in any of following ways……& try to get involved  with its vibrations. 
- OMmmOMmmOMmm...
- OMmmmmOMmmmmOMmmmm...
- OMmmmmmmmOMmmmmmmmOMmmmmmmm... 
6. Mantra Chanting 10 to 20 rounds 
It could be Gayatri mantra or  any other mantra chanting which would create great peace and make  your mind calm. 
Conclude the session by  offering gratitude to the Lord. Be silent & observe your  experience and feeling for 5 to 10 Min. Open eyes with awareness of  eyelashes, eyelid & eyeball. 
Benefits of the above are - 
One, it stimulates  the parasympathetic nervous system which helps to calm down. 
Two,  it enhances your strength & vitality of body & mind.
Three,  it connects mind & body through ultimate source of life i.e.  breathe.
Four,  it strengthens your mind to cope with any stressful situation in the  life.
Five,  the more slowly you breathe in and out the more serenity and  stillness you will feel. 
It  is said that slower the breathing rate more is the life span. In  support of this the following chart is given to show connection  between breathing rate & the life span of some of the animals.
      
      
      
      
        | Animal | Breathing rate,  breaths/min | Life span,  years | 
      
        | Tortoise | 4 | 150 | 
      
        | Whale | 6 | 111 | 
      
        | Elephant | 4-5 (lying down) | 70 -100 | 
      
        | Horse | 8-15 | 50 | 
      
        | Monkeys | 32 | 18-23 | 
      
        | Dogs | 20-30 | 10-20 | 
    
Lastly,  do Shavasan. Lie down in supine posture & keep relaxed all parts  of body. Surrender yourself completely to mother earth with  awareness. 
Finally,  experience enjoy and relax. 
Editor  - from personal experience suggest that a good way to manage anxiety  is to be detached to the cause of anxiety. If you are not getting  sleep then keep on chanting till you get sleep. When feeling  depressed do things that make you happy, recall events that enhance  your feeling of self-worth. Lastly, sit and meditate in silence. When  every am confused open any page of the Holy Gita. Sooner than later  the confusion has gone, I find answers. 
Author is B.A.M.S &  done Post Graduate Diploma in Yoga Shastra. She is working with  Kaivalyadhama Yoga Institute, Mumbai as Public Relation Officer &  Medical Consultant since last 7 years. She is also attached with  National & International institute of Yoga. In Mumbai she is  working with Sanskrit Peetham Yoga department of Somaiya College,  Vidyavihar and Yoga Sadhana Mandir, Nerul  as a visiting faculty  for teaching Yoga subjects. 
Also read
1. Do's and don'ts on  Yoga Asanas with photos
2. International Yoga Day  - common Yoga protocol
3. What do I gain from  meditation
4. Prayer and mantra jap  in Yoga