When correcting student errors, its best to keep the experience positive for the learner. Being corrected constantly can be a really de-motivating experience. Hence, as you listen out for students’ errors, you could also make sure to also listen out for really good uses of language and highlight these to the class too. Also, before beginning an activity, you could bear in mind whether you are concentrating on accuracy or fluency, since this helps identify if the correction would be instant or delayed.
As an alternative, authentic, tool to measure the progress over a period of time in various skills and contexts of English language you could create student portfolios. This form of assessment helps students and teachers to identify learning goals and demonstrate learning mastery. You could also create and employ the use of ‘rubrics’. These allow for the assessment of students’ work to increase in objectivity, consistency and efficiency.