In order to bookmark a spot in space just press "Ctrl-B" or you can also open the "People & Places" window and click the "Add Location" button at the bottom. Instead of that just fly to each belt and bookmark a spot in space where you have as many asteroids as possible within mining range and set the default orbit distance to something like 3500m in order to always keep asteroids in range and maximize yield. When setting up the mining spots bookmarks please remember that you must not bookmark the asteroid belts directly. This will make sure your damaged drones will start fully repaired at the beginning of each mining run. TinyMiner will right-click on your ship, select the "Get repair quote" option, then click the "Repair All" button and press Enter to confirm the payment. If you wish to use the "Repair Ship in Station" option then you need to resize and position the "Repair Facilities" window as shown in the screenshot above.
HOW TO CREATE A BOOKMARK IN EVE FULL SIZE
Starting up in station, your screen should be set up like in the picture at the bottom of the page (click it to open it in Full Size for comparison!).