In addition to the actual ingathering of the Jewish People to Israel, this prayer has an inner understanding of rectifying sexual sins.

The spilling of semen in vain causes innumerable souls to be scattered in all directions without a fitting body to receive them. Instead they are doomed to wander in exile among the kleipot. These outcast souls must be rectified and returned to their heavenly source.

In addition to the actual ingathering of the Jewish People to Israel, this inner understanding is one of the meanings of the blessing in the Amidah prayer, “Tekah b'shofar gadol.”  This should also be in our mind when we say, “Blow a great shofar for our freedom, and raise a banner to gather in our exiles, and gather us together speedily from the four corners of the earth to our land.”

At the end of the blessing, when you say the phrase "Yachad Marba Kanfot", meditate on the second to last letters of each word, Chet, Beit, Vav. These letters spell out one of the holy names of Hashem that is alluded to in the pasuk from Iyov (Job 20:15) "Chayil Bala Vayekiyenu" (He swallowed wealth, but will vomit it out). This idea alludes to the return of blessing and shefa power to a person, after it was removed to to sin.

{WARNING: Divine names should only be used in thought, DO NOT PURNOUNCE THEM, meditate on them in your minds eye for the best of your ability.}

Before you seal the Bracha say the following prayer:

May it be your will our G-D and the G-D of our fathers that every single drop of seed from me that went to waste, whether on purpose or by accident, whether it occurred through thoughts or actions, whether in this reincarnation or in a past reincarnation, and were swallowed up by the Klipot. Now the Klipot should vomit these sparks of seed that they had swallowed up, in merit of the awesome name coming from the verse "Might that they swallowed they will vomit" CHES<BAIS<VAV and in honor of your great name (combine the name YKVK with the name CBV YUD<CHES<HEH<BAIS<VAV<VAV<HEH.

Also in the simple translation of the blessing, have in mind that you are gathering all the sparks from the Klipot.

Do these kavanot three times a day in the amidah of all three prayers. You should occasionally leave out the prayer, to avoi making a permanent addition to the prayers set by our sages.