1. Ua ntej, lub keel yuav tsum tau nruab thiab kho nrog ib tug expansion yeeb nkab. Thaum kho, tag nrho cov theem kuj yuav tsum tau. Thaum cov yas ntoo phab ntsa raug ntsia rau hauv av, qhov saum npoo ntawm cov yas ntoo keel yuav tsum siab tshaj tus ntsia thawv hau ntawm lub hau;
2. Tom qab kho cov ntsia hlau, lawv yuav tsum ua raws li qhov chaw ntawm cov yas ntoo phab ntsa, kom tiaj tus, thiab qhov sib nrug yog li ntawm 3-5 hli;
3. Cov yas ntoo phab ntsa thiab keel yuav tsum tau kho nrog cov ntsia hlau thaum pib thiab qhov kawg, thiab kho nrog cov yas clips ntawm qhov sib txuas ntawm ob. Tom qab lawv tau kho tas lawm, xyuas dua seb lawv puas raug kho.