Multi tasking is a myth. When we do multitasking our brains switch the context and this context switching is very in efficient. You might have noticed it when you go read something online and get back to work. It takes some time to settle in and again get back into work. It seems as if brain has to unload things from what it read online, then load the data related to work to start working and this switching sometimes takes 10 to 15 minutes. If you try to switch again in this time, now there was no way for brain to work efficiently.
The best way so is to do only one thing at a time, complete it and then go to the next, complete it and then go to the next and so on. If you try working like this you will be more productive and also more peaceful and at ease with work. You will also have worked in a more focused way with the whole processing power of the brain available to complete that work. This should help do the work better. It also helps to have pride in the work you do - that way you try to make it the best you can.
There is nothing else to this. Just radically single task. Basically make a list of things in the order of priority that you want to do. Start with the first one. Finish it and start the second one till the time in the day is over or all your list is done! This will just guarantee that we don't get distracted at all. If you get distracted all you have to do is, just realize, recommit and then be back at what you're doing and restart the radical single tasking mode.
Try it - it will be beautiful.
This is called the Ivy lee method of productivity. See the full story in James' blog