I recommend reading through the Bible, at least once, and have continued exposure to it going forward.
Jesus promised,
"But the Helper, the Holy Spirit, whom the Father will send in My name,
He will teach you all things, and
bring to your remembrance all things that I said to you." John 14:26 NKJV
What happened to me early in my walk was the Holy Spirit would remind me of verses from different parts of the Bible (in context) and bundle them together to convey an idea, teaching, direction, etc.
That process became more casual over time.
I have a dilemma. I had a vision, and this vision authenticates me as the gate keeper to heaven, because I have the higher way that others merely dreamed of, they spoke through a glass darkly I speak because I have seen and see daily.
Now imagine I have this experience, no lsd, no obvious reason but this thing happens. How do I know it is from God and I am not just going nuts?
I would want confirmation from others that I am speaking from Jesus and scripture, that the whole revelation of God confirms my position.
I would then want to see how many others had similar experiences and what happened to them.
And I will discover man and pride wants so badly to be the prophet, the gate keeper, the revealer, and these revelations often lead to me having a few extra wives, breaking normal social boundaries, power and absolute authority were to disagree with me is to disagree with God, and if I go too far, something rather fatal occurs.
What grounds me in Christ is what the apostles said.
11 Make it your ambition to lead a quiet life, to mind your own business and to work with your hands, just as we told you,
12 so that your daily life may win the respect of outsiders and so that you will not be dependent on anybody.
1 Thess 4:11-12
15 But in your hearts set apart Christ as Lord. Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have. But do this with gentleness and respect,
16 keeping a clear conscience, so that those who speak maliciously against your good behavior in Christ may be ashamed of their slander.
1 Peter 3:15-16
Almost without fail false prophets and teachers condemn what went before as evil, empty, nothingness, and they are the fountain of truth alone or their group, and everything else is just a distortion, brain washing that the deluded follow. And for those disallusioned and despairing this sounds very attractive, except when the faith goes from the individual to the authority figure, because then boundaries can be crossed and things go from promise to exploitation.
Sadly the initial trigger may well be something real, ie a vision or dream, but its meaning is as random as the mind sometimes.
Let us list a few. Mohammed Muslims, Joseph Smith LDS, Charles Taze Russell JW.
These are the most successful, there have been thousands of others. Some say they are Jesus, some a prophet, some a priest all find some deeper meaning in the texts that others have missed, or a new revelation from an angel etc.
Paul himself feared he was in error.
2 I went in response to a revelation and set before them the gospel that I preach among the Gentiles. But I did this privately to those who seemed to be leaders, for fear that I was running or had run my race in vain.
Gal 2:2
Paul founded his whole ministry on a vision, confirmed by prophets, and anointed by the church. So there is nothing wrong with visions held in unity with Gods word and His people.