Here are some classic (literally) rules on preaching by John Wesley
1. Be diligent. Never be unemployed. Never be triflingly employed. Never while away time, nor spend more time at any place than is strictly necessary.
2. Be serious. Let your motto be, ‘Holiness to the Lord.’ Avoid all lightness, jesting, and foolish talking.
3. Converse sparingly and cautiously with women, particularly with young women.
4. Take no step towards marriage without solemn prayer to God and consulting with your brethren.
5. Believe evil of no one unless fully proved; take heed how you credit it. Put the best construction you can on everything. You know the judge is always supposed to be on the prisoner’s side.
6. Speak evil of no one, else your word, especially, would eat as doth a canker; keep your thoughts within your own breast till you come to the person concerned.
7. Tell every one what you think wrong in him, lovingly and plainly, and as soon as may be, else it will fester in your own heart. Make all haste to cast the fire out of your bosom.
8. Do not affect the gentleman. A preacher of the Gospel is the servant of alL
9. Be ashamed of nothing but sin; no, not of cleaning your own shoes when necessary.
10. Be punctual. Do everything exactly at the time. And do not mend our rules, but keep them, and that for conscience’ sake.
11. You have nothing to do but to save souls. Therefore spend and be spent in this work. And go always, not only to those who want you, but to those who want you most.
12. Act in all things, not according to your own will, but as a son in the Gospel, and in union with your brethren. As such, it is your part to employ your time as our rules direct: partly in preaching and visiting from i house to house, partly in reading, meditation, and prayer. Above all, if you labour with us in our Lord’s vineyard, it is needful you should do that part of the work which the Conference shall advise, at those times and places which they shall judge most for His glory.