If you are using wordpress.com, scroll down the bar of options on the left. Select Appearance – Themes, view a selection of options re. the format of your blog and go for the one you are most happy with.
Then, continuing with the left hand options bar, go to Appearances – Widgets, and ‘drag’ across the widgets you have selected (as explained by the notes on the site). If you hit problems enter a comment and I will seek to respond within a week. NB I am new to this! . . . just a week in! but seeking to share whilst it is fresh and current in my mind/understanding . . . . . .
You can then add photos and videos/u-tube links, PowerPoints etc by clicking on the relevant icon at the top of the edit box.
All the best! Acknowledge totally my blog could be much more complex; 7 days in and much to learn! . . . .
Here are some blogs you can have a look at to inspire you (their views may or may not be mine, suggesting for format and different styles etc. In no particular order):