pagal + accusative

1. Following something. Pagal names the plan, rule or model that an action follows:

• Viskas vyksta pagal planą. (Everything is going according to plan.)
• Kepiau pagal močiutės receptą. (I baked following Grandma's recipe.)
• Žaidžiame pagal taisykles. (We play by the rules.)

2. Sorting by something. Pagal also names the measure you sort or arrange by: Surūšiuokite knygas pagal dydį (Sort the books by size).

3. Useful phrases. pagal tvarkaraštį (on schedule, by the timetable), dirbti pagal specialybę (to work in the field you trained for).

4. Always the accusative. Pagal is one of the prepositions that take the accusative, like per and apie: pagal planą, not pagal plano.

5. Not for opinions. When reporting a person’s words, prefer anot jo or pasak jo for English according to him. To report someone's words, use anot or pasak + genitive: Anot straipsnio autoriaus, ... (According to the author of the article, ...). For your own view, say mano nuomone (in my opinion) or man rodos (it seems to me). For a personal opinion, mano nuomone is the recommended wording. Source-reporting phrases with pagal are also encountered, but are a secondary norm variant.