This post will address the question from the perspective of a member of The Church of Jesus Christ of Latter-day Saints; most of the principles though are consistent with beliefs found in many Christian faiths.
#1 - Repentance
The Holy Ghost speaks with a still, small voice; the natural man screams very loud. We can easily put ourselves in a position where we are not in tune with the Spirit and cannot readily receive its promptings. Like an old-fashioned radio, if we are having trouble picking up the signal, before we assume the broadcast tower is broken, we do well to examine our receiver.1
In the Sermon on the Mount, Jesus specifically identified 2 of the most common, natural-man tendencies, that are at odds with God's nature and will therefore drive away the Holy Ghost:
21 Ye have heard that it was said by them of old time, Thou shalt not
kill; and whosoever shall kill shall be in danger of the judgment:
22 But I say unto you, That whosoever is angry with his brother
without a cause shall be in danger of the judgment: and whosoever
shall say to his brother, Raca, shall be in danger of the council: but
whosoever shall say, Thou fool, shall be in danger of hell fire. (Matthew 5:21-22 -- note that there are arguments that the words "without a cause" are not in the original text)
AND
27 Ye have heard that it was said by them of old time, Thou shalt not
commit adultery:
28 But I say unto you, That whosoever looketh on a woman to lust after
her hath committed adultery with her already in his heart. (Matthew
5:27-28)
Anger & lust are very effective at limiting our spiritual reception.
A strong caution is given by King Benjamin:
And now, I say unto you, my brethren, that after ye have known and
have been taught all these things, if ye should transgress and go
contrary to that which has been spoken, that ye do withdraw yourselves
from the Spirit of the Lord, that it may have no place in you to guide
you in wisdom's paths that ye may be blessed, prospered, and
preserved-
I say unto you, that the man that doeth this, the same cometh out in
open rebellion against God: therefore he listeth to obey the evil
spirit, and becometh an enemy to all righeousness; therefore, the Lord
has no place in him, for he dwelleth not in unholy temples. (Mosiah
2:36-37)
We can limit our ability to receive the Holy Ghost through our own choices -- the antidote to this is repentance. When we bring our lives more in harmony with the Lord's teachings and keep the natural man in check we will better be able to understand spiritual things:
14 But the natural man receiveth not the things of the Spirit of
God: for they are foolishness unto him: neither can he know them,
because they are spiritually discerned. (1 Cor. 2:14)
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#2 - The Parable of Growing a Tree
There is a full sermon in the Book of Mormon that addresses this subject. Alma compared the word of God to a seed that grows into a great tree. A few key passages from Alma 32:27-43 below (emphasis mine):
But behold, if ye will awake and arouse your faculties, even to an
experiment upon my words, and exercise a particle of faith, yea, even
if ye can no more than desire to believe...
Now, we will compare the
word unto a seed. Now, if ye give place, that a seed may be planted in
your heart, behold, if it be a true seed, or a good seed, if ye do not
cast it out by your unbelief, that ye will resist the Spirit of the
Lord, behold, it will begin to swell...as the seed swelleth, and sprouteth, and beginneth to grow, then
you must needs say that the seed is good...And now, behold, because ye
have tried the experiment, and planted the seed, and it swelleth and
sprouteth, and beginneth to grow, ye must needs know that the seed is
good...
...and now behold, after...[this] is your knowledge perfect? Behold I
say unto you, Nay; neither must ye lay aside your faith, for ye have
only exercised your faith to plant the seed that ye might try the
experiment to know if the seed was good...
And thus, if ye will not nourish the word, looking forward with an eye
of faith to the fruit thereof, ye can never pluck of the fruit of the
tree of life. But if ye will nourish the word, yea, nourish the tree
as it beginneth to grow, by your faith with great diligence, and with
patience, looking forward to the fruit thereof, it shall take root;
and behold it shall be a tree springing up unto everlasting life.
(See the full passage for a more detailed discussion of the experiment Alma recommends).
The criteria to try Alma's experiment are simple:
- A particle of faith
- A mere desire to believe
- Diligence
And then he asks people to put God's words to the test. This principle is taught succinctly by the Savior in John:
If any man will do his will, he shall know of the doctrine, whether
it be of God, or whether I speak of myself. (John 7:17)
Note that this isn't an invitation to try something indefinitely until it succeeds. This is an invitation to live the Christian life, keep the commandments, and put in practice the Lord's teachings, and then see the results that come from it.
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#3 - Ask, and Expect Personal Revelation to be Personalized
Nephi taught that God speaks to people in a manner they understand.
For my soul delighteth in plainness; for after this manner doth the Lord God work among the children of men. For the Lord God giveth light unto the understanding; for he speaketh unto men according to their language, unto their understanding. (2 Nephi 31:3)
To someone with a highly logical mind, God may teach things logically. To someone who learns through patterns, God may teach by showing patterns. I teach my own children in different ways based on what helps them learn. God is a way better father than I am and He is a master of this principle.
Finally, the invitation oft-repeated in the scriptures is simple: Ask.
Ask, and it shall be given (Matthew 7:5)
If any of you lack wisdom, let him ask of God, that giveth to all men liberally (James 1:5)
If one is seeking to be worthy of the influence of the Holy Ghost and diligently trying to live after the pattern the Lord has given, why not ask God in prayer what inspiration from the Holy Ghost feels like?
1 I certainly do not claim perfection in this regard. When I find that I am struggling to receive the influence of the Holy Ghost, invariably I find that I have been slack in doing things which invite the Holy Ghost.