A lovely little thing that occurs is street preaching and something I have not seen one for a while. A few months ago by now a person preaching gave me a little card saying I have the choice to go to Heaven or Hell. I reminded myself of this card and took a bit of time to think, a lot of the street preachers I have came across seem rather weak in their arguments and preparedness, leaving little to no impressions. For this reason, I'll try to give Christian's some advice as to how to be better at preaching.
If there is one thing that should certainly be done, it is to not threaten with Hell as punishment. This is probably done too often, especially without mentioning the rewards of being a good Christian. Why not tell people what will happen if they convert to Christianity and behave as what a Christian should according to the Bible? Besides this, a lot of people do not believe in Hell, so threatening them with such makes the threat void.
With trying to induce fear, a lot of people won't fall for it. Going up to me and saying I will go to Hell isn't going to make me soil myself in fear of punishment. If anything, straight out going up to a person and saying they'll go to Hell is not a good idea as one street preacher thought it would be. I thought it was rude and just moved on without saying a word to him, other people may not be so forgiving.
I have talked to a few street preachers, but with some they show absolute ignorance of other religions. A preacher once asked if I believed in God and when I told him "No" he immediately asked if I was a Muslim. This man obviously doesn't know what he is doing. Anyone who understands Islam know Muslims believe in God, so this preacher immediately lost credibility. People may not have an experts knowledge on a religion but many will not be stupid enough to miss a lie or mistake told about a religion. So learn about other religions, it will create knowledge and it gives a good impression.
If anything makes people want to punch a person in the face or verbally beat them senseless is insults. All insults will do is create unneeded tensions and confrontations, so avoid insulting anyone or anything (especially religions in general and peoples personal beliefs). It looks petty, and like with telling a lie or making a mistake it can make credibility disappear quickly.
There is always that one person with strong faith in their beliefs, sadly some Christians believe only followers of Christ can hold strong faith. This isn't the case and stating so can be an easy way to begin a fight. There are many non-Christians who hold their beliefs in high faith, so if such a person comes along pushing their buttons won't be a way to convince the person to convert.
Many preachers I have come across seem to have wanted to show an imaginary badge, that they are Christians and this somehow makes them important. It is overall just an arrogant feel and makes them seem the opposite of genuine when it comes to the concern of a persons afterlife. When a preacher is genuine in trying to convert people to Christianity, it should show. If a person cannot be genuine when they preach their religion, either they need to assess what they are doing or find something better to do.
Many people haven't read the Bible, with Christian's in particular having a reputation for this. Others lack of reading and even knowledge of the Bible isn't an excuse to be lazy. If street preaching is to be done, constant studying of the Bible is going to be a must to gain great knowledge of the texts contained within. Knowing a verse or two isn't going to help when asked about such things as punishing children with death (Leviticus 20:9, Exodus 21:15) or how new ethnicities can arise through incest (Genesis 19:30-38).
A personal pet peeve of mine is when street preachers use their young children to preach, this is mainly done not by them talking about the Bible but rather handing out pamphlets. Asking difficult questions is going to happen eventually, and the kid will likely be unable to give a proper answer due to a lack of understanding of the Bible thanks to one factor, young age. Doing such a thing can look very lazy and seem irresponsible as a person can potentially give a very negative response. Preaching should probably be left to the teenagers and adults, as both are a lot more likely be able to properly understand what the Bible states.
Hopefully this will be useful for whatever street preacher that may read this. It is probably strange for a non-Christian to give advice on how to convert people to Christianity, but sharing information, giving tips and helping one another shouldn't be restrained based on differing views.