The best way is to look at the signs Jesus said would happen when he is at the door. While it is true no one can know the exact hour he will come, BUT he also said believers will know when he is at the door by spotting the signs he listed in the bible, so it we see many of these signs happening, it is pretty clear we can we trust the word of God and he IS at the door. Pretty simple IMO.
End times teaching such as “he is at the door” is pretty close to “the Time draws near” as Jesus told us to avoid so that doesn’t help. saying “he is at the door” is like saying “any day or moment now”, the “signs” you speak of can apply to ANY event in any point and time in history, the Bible is not a crystal ball Jesus said wars,distastes, and such are just stuff thats gonna happen in the world.
“But do not ignore this one fact, beloved, that with the Lord one day is as a thousand years, and a thousand years as one day. The Lord is not slow about his promise as some count slowness, but is forbearing toward you, not wishing that any should perish, but that all should reach repentance. . . . Since all these things are thus to be dissolved, what sort of persons ought you to be in lives of holiness and godliness, waiting for and hastening the coming of the day of God, because of which the heavens will be kindled and dissolved, and the elements will melt with fire! But according to his promise we wait for new heavens and a new earth in which righteousness dwells. Therefore, beloved, since you wait for these, be zealous to be found by him without spot or blemish, and at peace” (2 Pet. 3:8–14)
In others words don’t say “he’s right at the door, look at the signs!” thats practically rushing God to bring the end of the world. Just live your Christian life (confessing, be a good neighbor, be the best you can be ect.) and worry about the end when it comes, dont rush God, the world will end at his desire, not ours and saying “he’s right at the door” is no exception