if im going to be honest the best thing to do 1 imputictular topic and practice its through past papers so like 1 week you practice just skills questions and just by doing it repeativley it should really help. Heres afew links that might help.
https://www.studyclix.ie/discuss/Junior-Cert-Material-Technology-Wood/woodwork-short-notes
http://www.t4.ie/Resources_JC/MTW/MTW%20workbook%201.pdf