How do you catch the Holy Spirit?

Answer 1

You can't. Jesus decides who He wants to give the Holy Spirit to.

Roman Catholic AnswerYou "catch" the Holy Spirit through worthily reception of the Sacraments. This is the way in which Jesus set it up for us to receive grace. Specifically, the sacraments of Baptism and Confirmation are the Holy Spirit. But we receive the Holy Spirit in all the Sacraments. To do this we must receive them worthily (in a state of grace), aside from the sacraments of the dead, like Baptism and Penance which are specifically designed to give us grace when we are dead in our sins, in order to bring us out of that state.

Answer 2

the best answer to that would be to get Confirmed and understand your faith. :)

First you must have the Holy Spirit indwelling you:

Eph 1:13 And you also became God's people when you heard the true message, the Good News that brought you salvation. You believed in Christ, and God put his stamp of ownership on you by giving you the Holy Spirit he had promised.

Then you must be obedient to the Holy Spirit as the Spirit works in you:

Php 2:13 because God is always at work in you to make you willing and able to obey his own purpose.

Answer 3

People get the holy ghost when a woman of god or a man of god lays hands and imparts it inside of you and you are ready and clean and willing to receive it.