If live in Southeast Asia and you want to harvest your own tongkat ali plant, you need to find one which is mature. Tongkat ali plants usually bear fruit when they are 2-3 years old, and you should harvest the plant when it is no more than 4 years old. When a Tongkat ali plant is ready to harvest, it may have small red or pink flowers, or it may have fruit which starts out green and darkens to red. You may have to dig a hole in order to get the whole root without it breaking, since tongkat ali roots usually grow straight down into the ground. If you want to make your own extract but you don’t live in an area where tongkat ali grows naturally, you can order whole roots online. Even if you order your plants online, it’s a good idea to wash the root in cool water before you use it, just as with any other vegetable or herb you intend to consume. Eating unwashed fruits and vegetables can cause severe diarrhea and other illnesses, especially if you are visiting from another country. Traditionally, tongkat ali roots are dried in the sun for several days. However, you can get the same effect by drying the roots in an oven set to 100–120 °F (38–49 °C) for about 72 hours. To dry your tongkat ali in the sun, lay it flat in a warm, dry place that receives at least 5-6 hours of full sun a day. It may take 3-5 days for the root to dry, or a week or more if you live in a place with high humidity. Once the root is thoroughly dried, slice it into rounds as thinly as possible. Place several slices into 2–3 cups (470–710 mL) of water, then boil the mixture for about 20 minutes. Although you can slice your tongkat ali before the drying process, it's easier to cut evenly once it has been dried. Discard whatever you don't drink. You can repeat this up to 4 times a week. Traditionally, the same tongkat ali root may be boiled up to 3 times.

Summary:
Choose a mature plant that is flowering or bearing fruit. Pull up the whole tongkat ali plant to access the root. Wash the roots thoroughly. Dry your tongkat ali roots by placing them in a 100–120 °F (38–49 °C) oven. Slice the tongkat ali root thinly then boil it. Drink the mixture as soon as it has cooled.