The opening 6 verses from Ecclesiastes chapter 11 give us encouraging lessons in evangelism.
Verse 1 - Cast your bread upon the waters: for you shall find it after many days.
This gives us the basic exhortation to spread the Gospel - the Bread of Life, John 6 v 35.
Verse 2 - Give a portion to seven, and also to eight..... is a reminder to spread this bread liberally, that is freely, without reserve, as much as possible and as often as possible.
Verse 3 - If the clouds be full of rain they empty themselves upon the earth: and if the tree fall toward the south, or toward the north, in the place where the tree falls, there it shall be. This speaks to us of divine providence. God arranges circumstances so we get opportunities to give the Gospel to people in situations that we least expect.
Verse 4 - He that observes the wind shall not sow; and he that regards clouds shall not reap. We can always make excuses for not sowing the seed of the Gospel. When we determine to spread the word, the Devil will fill our minds with all manner of "reasons" to delay, or avoid, doing the business.
Verse 5 - As you know not what is the way of the spirit, nor how the bones do grow in the womb......even so you know not the works of God who makes all. The word for spirit is wind; see John 3 v 8. Just as the wind blows where it wishes, so the Holy Spirit blows into peoples' lives to convert them. We do not know how God is working His purposes out in the people we meet.
Verse 6 - In the morning sow your seed, in the evening withhold not your hand: for you know not whether shall prosper, either this or that, or whether they both shall be alike good. As we sow the seed of the Gospel we need to be aware that the most unlikely people will get saved. We simply do not know what is in peoples' hearts when we give them the truth.