。
After school, I usually play baseball.
Literal
I [topic-は] after-school [at-には] usually baseball [object-を] do.
放課後 ('after school,' a compound noun) + には (temporal marker with contrastive/emphasis は). たいてい ('usually, mostly') is a frequency adverb. 野球をする ('do baseball' = play baseball) is the standard light-verb construction — Japanese says 'do' for most sports rather than 'play.'