This sequencer is based on a PicAxe. PicAxe programming language is quite easy to learn.
Many circuits exist for sequencers........ Here's one I find very useful, that is built around a PicAxe as opposed to a comparator type IC. This way the delay between the different stages can be individually set as opposed to a standard Capacitor / Resistor combination.
It is all very basic and nothing new, but it's what I use and it works very well giving me a lot of flexibility in the timing. For those with Eagle, it would be VERY easy to shrink the board down substantially!