i used to have the same problem (now my problem is getting past the first levelĀ
), and I found harrington on holdem vol 2 helped a lot, where it talks about inflection points and playing against rising blinds - it uses the ratio of your chips to the total of the SB and BB and discusses what to do when... very useful imo.
Definetely give it a go. I read Volume 1 and was very impressed, didn't realise the second volume was available. Thanks