按照(àn zhào) - according to, in accordance with, following in Mandarin

按照 (àn zhào) introduces the rule, plan or standard you are following: 按照计划 (àn zhào jì huà) according to plan, 按照规定 (àn zhào guī dìng) as the regulations state, 按照顺序 (àn zhào shùn xù) in order.

It is close to 根据 (gēn jù), and in many sentences either works. The useful split is that 按照 (àn zhào) points at something you comply with, while 根据 (gēn jù) points at something you draw a conclusion from. You act 按照 (àn zhào) the instructions; you judge 根据 (gēn jù) the evidence.

Two habits keep English speakers on track. 按照 (àn zhào) comes before the verb phrase, not after it, so the shape is 按照计划出发 (àn zhào jì huà chū fā) and never the reverse. And it takes a noun, never a clause: to say according to what he said, you need 按照他说的 (àn zhào tā shuō de), with 的 (de) turning the clause into a noun.