These are some things I've learnt about managing my tasks effectively.

Collect your tasks

Dump your tasks in your to-do list the moment you get them. It's important not to lose any.

It's equally important to not jump directly into execution mode. It helps to spend some time thinking about the task to tackle it effectively.

All tasks in one place

Avoid using multiple to-do lists. You should be able look at all your tasks in a single place.

Something like Trello is the perfect tool for the job. Create a list named Unallocated to collect your tasks before you review them.

We get tasks from a variety of places. You should be able to route all your tasks to your to-do list in an effortless manner.

Email

Check your email only once every two hours. Context switching can really hurt your productivity.

Run through every email and follow this simple framework -

Everything else

Use the home screen widget of the Trello mobile app to quickly add any task

Review your tasks

Look at your tasks atleast once every day and think about each one which needs your attention.

Try to answer these questions -

Classify your tasks

I'd recommend using the Eisenhower matrix to classify your tasks.

Create these 4 lists in your Trello board -

Miscellaneous tips