Before you plant your seedlings, you will need a nutritious soil mix for them. (This is a picture of the soil before water is added).
Add water to the soil. The mix should have the consistency of cake batter, and should not be too wet.
Put the soil into pots. The pots should be full to the top, as shown in the pots at the bottom of the picture. The pots in the back of the picture need more soil.
In order to transplant the seedlings, they must have their first set of true leaves. These tomato plants only have cotyledons, the first leaves to grow (not to be confused with the first TRUE leaves).
These parsley plants are perfect for transplant. You can see the small cotyledons towards the bottom, but the true, more shaped leaves have grown.
Poke holes in the soil for the seedlings to be transplanted in. It is important to make sure the holes are directly in the center of the pot.
Next, remove the seedlings from each other. If two plants are intertwined, carefully separate them from one another. Some roots breaking is inevitable, so don't stress... just use gentle hands.
Planting the seedlings is important; if they are buried incorrectly, it will affect how they grow. In this picture, a seedling is buried too deep in the soil. This is the wrong way to transplant them.
Here, the plant is not buried too deeply. When transplanting, make sure the roots are fully covered, but be sure that the plant is not buried deeper than where the roots turn to green.
After transplanting, the seedlings will be under some stress. Before putting them in full sun, put them out of direct sunlight for 24 hours. After that, your seedlings are ready to grow normally.