The book "Rise Up Singing" has a useful chord format in which the chords are written out in a row at the end of the song (or occasionally in the middle e.g. for a bridge). There is an indicator for each beat - or sometimes each half beat - or sometimes every second beat - depending on how rapid the chord changes are. A dash means you repeat the previous chord; a slash marks the end of a line. So for example: A - D A / E --- / means: line one plays A A D A; line two plays E E E E. There are other notations e.g. for repeated bars, or extra chord changes in between, etc. It's really extremely simple to learn & use. The book is easily available, & an excellent general resource, as well.