Select vegetables you wish to grow, then research herbs that make good companion plants for those vegetables. Research the specific vegetables and herbs you intend to grow, taking note of their moisture, light and temperature needs, as well as how large each plant becomes at maturity. Purchase starter vegetable and herb plants or purchase seeds in each variety of plant you wish to grow.
Clear a sunny, well-drained spot. Till the soil and remove weeds as needed. Mix some compost or other fertilizer into the soil. For container gardens, choose containers appropriate to the herb/vegetable pairings you chose. Fill the containers with a high-quality potting mix and work some compost or other fertilizer into the mix.
Carefully transplant starter vegetable and herb plants into their containers or garden holes, being careful not to damage the plants' delicate roots. Place your vegetable plant into the hole, then place the herb plant in right next to the vegetable plant. Carefully surround both plants with garden soil, making sure the plants are securely transplanted into their containers or holes. For seed planting, simply sprinkle a few vegetable seeds into the container or garden soil, then sprinkle the herb seeds in the same way. Lightly cover your seeds with soil and water thoroughly.
Water plants daily, fertilizing when necessary according to package directions on the fertilizer. Weed the garden as needed, and keep an eye out for garden pests such as animals or insects that may harm your plants. Take appropriate measures to eliminate the pests as needed. Harvest your plants once they reach maturity. Research your plants to determine when maturity is for each individual plant. Remember, when harvesting herbs, never harvest more than one-third of the plant to keep it healthy and producing.