Formatting Text in Excel Spreadsheets

The general shortcuts for bold, italic and underline. They are Control + B, Control + I and Control + U. These work in Excel too! You can select text and change it when editing a cell. Or you can just position on the cell and change the format for the whole contents. If you want to also change the font, font size, colour etc, press Control + Shift + F for all the font settings in Format Cells dialogue. Tab around the settings, use Arrow Keys to change things and Spacebar for tick boxes. Press Enter to perform the changes and return to your spreadsheet.
There are also settings in the Format Cells dialogue for Number, Alignment, Border and Fill (shading). Press Control + Tab to move to these other pages of settings.