(1) Ua ntej saib ntawm qhov chaw tiav thiab dawb.
(2) Coj tus qauv thiab tso nws. Cov uas yooj yim tawg yog feem ntau cov khoom muaj calcium. Tau kawg, nws muaj peev xwm ua tau raws li koj qhov yuav tsum tau ua thiab tus nqi raug.
(3) Coj tus qauv thiab nqis rau ntawm ntug ntawm cov yeeb nkab kom pom tias nws tuaj yeem tawg, lossis qhov elongation ntawm kev tawg tom qab tawg.
(4) Nws yog teeb meem heev ntawm huab cua tsis kam. Txoj kev ncaj ncees tshaj plaws yog muab tso rau hauv qhov chaw uas muaj qhov kub thiab txias siab rau ob peb hnub kom pom qhov hloov pauv ntawm qhov chaw, tab sis nws yog nkim sijhawm. Cia li saib thawj 3 yam khoom.