You start out with 7 villagers. You can get 8 by either feeding a savage boy (he eats 500 food but you can never get negative food number) or having the 2 adults have a baby. Followed the tutorial: Make fire, train the teen to do science or farming, and train the 2nd adult who isn't a builder to do either science or farming. Have children collect butterflies, shells, and mushrooms. Additional butterflies and shells that are already in your collection give you 100 new tech points each.
After the tutorial: Have an adult or teen study all the herbs and flowers on the island. Once they are all mastered, you get credit for Puzzle 5. Improve your builder's skills by building the hut and repairing the broken hut. You do not get any puzzle credit for either of these, but you do get to increase your population past 8 for the first hut.
The first technology you want to purchase is farming. This lets your villagers climb the coconut trees. After you have purchased the farming technology, you can let the game run in the background about 2-4 hours (while you take a walk, do chores etc). The second technology you want to purchase is engineering. This lets you build the dam that will water the dry field.
After the dam is built, it takes some time for the crops to grow (if you click on the field it will tell you how long). You need an adept farmer to build the scarecrow. Now you can let your game run overnight if you need to. The third technology to purchase is exploration. This gives you a cauldron and metal. You need a master scientist to make the cutting tool. Once you have the cutting tool, you can now cut down the thorns around the toothy looking cave.
Anyway, that's how far I've gotten so far. Have fun!