As a general rule, the scion seed, which is selected for its fruit, should be planted earlier than the rootstock seed, selected for other qualities such as disease resistance. You can plant at more precise times if you know the growing rate of each variety. Plant in small containers. For this method, you will need to attach the two plants while each is still attached to its own roots, so they need to be able to reach each other without being transplanted. The first leaves to emerge from a seedling are small seed leaves that do not look like the leaves of an adult plant. After one or two of these have grown, a true leaf with a noticeably different shape will grow. When both plants are at this stage, they are ready to be grafted together. You'll have the highest chance of success if the stems of each plant are almost the same diameter and height, although it's not absolutely vital for this method. You should cut approximately halfway through the stem, with a sharp downward cut, between a 30º and 60º angle. Choose a point on the stem below the seed leaf. Always use a sanitized razor blade and wear latex gloves. This reduces the chance of infection to the plant. Because the cut requires precision, an ordinary sharp knife does not work as well for this method. Again, choose a point below the seed leaf and cut approximately halfway through the plant. The cut you make should be angled upward so the two cuts can easily be joined together. Hook the upper "tongue" of the scion plant into the wedge created by the cut in the rootstock plant. Secure the joint with a grafting clip or by wrapping it in lead tape. Labeling each plant at this point is a great idea, especially if the varieties look similar. If you get them confused in the next step, you could end up removing the best part of each plant instead of the worst. Unlike the top grafting method, you do not need to place your new hybrid plant in a special healing chamber, since each plant is still able to transport water from its own roots to its leaves. Keeping them...

TL;DR in Indonesian:
Tanamlah benih untuk cabang atas 5–7 hari sebelum benih cabang bawah. Bersiaplah mencangkok saat kedua tanaman telah menumbuhkan daun sejati. Gunakan pisau silet yang tajam dan bersih untuk membuat sayatan mengarah ke bawah pada setengah bagian batang bawah. Buatlah sayatan mengarah ke atas dengan sudut sesuai sayatan cabang atas. Hubungkan kedua tanaman pada posisi sayatan dan sambungkan. Tunggulah hingga tiap sayatan sembuh sempurna. Buanglah bagian atas tanaman cabang atas setelah lima hari. Buanglah akar pada batang cabang atas setelah beberapa hari. Lepaskan penjepit atau pembungkus.