Watering- Pepper seedlings need to be watered consistently, but they do not like waterlogged soil. Allow the topsoil to dry out a little between watering, but never completely dry out.

Lighting- If pepper seedlings don't get enough light, they will start to grow leggy and reach for the nearest window. So to make them grow thick and compact, it's best to use a grow light.

Fertilizers- Once true leaves begin to form, it's time to start fertilizing. But don't give them a full dose right away. Use a weak dose at first and slowly increase the strength as they get bigger.

Use (and highly recommend) Microbe mix with water and spray. 

Seedlings transplant. When the seedlings are 5-6 cm tall, transplant them into individual 7.5 cm pots filled with compost.

Carefully remove the seedlings from their original pot and tear apart the root ball. In each new pot, make a hole in the compost and lower the seedlings into place, holding them by the leaves. Firm the compost around the roots and water. Return the plants to a greenhouse or sunny windowsill and keep the compost moist

Pinch off Pepper Flower. specifically the buds and flowers – he prunes them to grow stronger roots and produce more chilies. To pinch, hold the pepper flower between two fingers and pinch it. Pinch the plants when they are indoors and stop when they have been in their outdoor containers for at least three weeks. You can harvest peppers in the unripe green or purple stage, but the flavor will be sweeter if you wait until they reach a ripe color – usually red, but sometimes golden yellow or orange.