Ascertaining the timing of an event is generally considered as the most daunting task in the Vedic Astrology, In other words the interpretation of the dashas requires the simultaneous application of many concepts hence is always a vulnerable area for any beginner or for that matter astrologer himself.
There are various methods for interpreting the dashas, but here I would like to take up one very interesting and accurate concept which would help all of you to enhance your accuracy levels in predicting events.
So coming to the method:
Step 1: Identify the event for which you wish to predict, suppose you wish to predict w.r.t the marriage timing of a person.
Step 2: Identify the corresponding bhava (house); the bhava used for deriving marriage related information is 7th.
Step 3: Now you have to identify the Jeeva and Sarira planets for 7th house.
There are 3 accepted methods for deriving jeeva and Sarira planets of a bhava (house):
1) The Lord of the Nakshatra (constellation) in which 7th lord (as per cusp lordship) is placed will become your Jeeva planet and the lord of the Nakshatra in which jeeva planet is placed will be your Sarira planet. For example Venus is my 7th lord, which is placed in the nakshatra of mercury, so mercury become my Jeeva planet for 7th house and mercury is placed in the nakshatra of Jupiter, so Jupiter becomes the Sarira planet for 7th house.
2) The lord of the sign in which 7th lord (as per cusp lordship) is placed will become your jeeva planet and the lord of the sign in which your jeeva planet is placed will become your Sarira planet. For example my 7th lord is placed in the sign of mars, so mars becomes my jeeva planet for 7th house and mars is placed in the sign of Jupiter, so Jupiter become my Sarira planet for 7th house
3) The lord of the sign in which karaka of the bhava (here it is the karaka of 7th house i.e. Venus) is placed will become your jeeva planet and the lord of the sign which is coming the 7th bhava from karaka will become your Sarira planet. Here we have counted 7 because we are considering 7th bhava, if you have taken 10th bhava, then you would have counted 10th bhava from the 10th karaka. For example Venus is the karak of 7th house, My Venus is placed in the sign of Mars, so mars becomes my Jeeva Planet for 7th house and lord of the 7th house from venus is venus only, so Venus become my Sarira planet for 7th house
Points to be noted:
1) Ideally you should use all the 3 methods simultaneously and should consider the strongest Jeeva and Sarira planet for the bhava.
2) The planets which are placed with Jeeva or Sarira planets or in simple words influencing them in a strong manner, then that influencing planet could also take up the role of jeeva or Sarira planet. So you have to do lot of practice to determine the actual jeeva and Sarira planet for the bhava.
So from the example you can see that from 1st method, my Jeeva and Sarira planets are Mercury and Jupiter respectively.
From 2nd method, my Jeeva and Sarira planets are Mars and Jupiter respectively.
From 3rd method, my Jeeva and Sarira planets are Mars and Venus respectively.
Now once you have all the above results, just look out for the most dominant planets out of them, see which of them can influence 7th house to the maximum level.
Also see whether or not there is any other planet (Apart from mercury, Jupiter, mars and Venus) which is influencing these jeeva and Sarira planets and is willing to take over the role of jeeva and Sarira planet.
So once you are able to identify the right or I should say the strongest jeeva and Sarira planet for the bhava, then you just have to focus on the Mahadasha, antardasha and parayantar dasha of the jeeva and Sarira planet. In those very mahadasha, antardasha and parayantar dashas an event would take place; in this case that event is marriage.