You need to monitor the temperature of the developer for consistency to allow repeating a print. The data sheet for the developer should give you a range to stay in and times.
You need to keep the print in the developer for sufficient time for a 'solid' black. I need to use a kitchen timer and not pull it out early. Otherwise I snatch.
You need to do a test strip for each of contrast and exposure with a new dev or paper.
Or rather I need to.
And you need to pick an easy negative eg with correct exposure so that there is silver in the shadows.
You need to expose the negative at half box speed until you are happy with your print shadows.
Pushing ISO is ok if you like the print signature you will get.
You need to keep trying.
Use a small paper size cause you will need to reject a lot of prints if you are self critical.
It is hard starting up from scratch by yourself.
http://www.kodak.com/global/en/professional/products/chemistry/bwPaperProcessing/dektolDeveloper.jhtml?pq-path=14045
http://www.ilfordphoto.com/applications/page.asp?n=34
