Well I have managed to create a tag cloud so will try to explain here how I have done this.
a) A delicious account is created and items on the web are saved to it through the tag option toolbar button which comes with delicious. This first part should be easily worked out when you download delicious from the web.
b) When items are added to delicious you are given an option of creating your own tags for these item. That is create key words which mean something to you for the items you are saving. It is best to try to match these tags with other similar items, like a filing system.
c) when you open delicious you will see a setting option on the top right side, next to your user name. Open settings
d)You now have a variety of options (I do not know what they all are). Third column along is tags. I chose to bundle tags. ( I do not know if you have to do this prior to creating a cloud. I think this is a separate option). If you click on this you can now select major file names for your tags. Once you select a category name you can click on your tag names that appear there and they will file into that bundle name. You then click save and those tags are grouped in the particular category, I chose Midwifery, Research and E-learning for mine, but I might change these.
e)In the fifth and final column along you will see an option, third down for tag rolls. Click on that and it will bring up a tag cloud. you can now change the size of the font etc by using the slide gauges.
f)Select the 'embed link' and copy this.
g) open your blog and go to customize. Select add a page element and choose html/java script and hit add to blog.
h) paste the embedded link in the window, choose your title and you are done.
Hope this helps those who are trying to do this.