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If you are stuck without a measuring device, it can be useful to have some visual aids in your head as a reference for the correct amount. Here are some good ones to remember: A teaspoon is about the size of the tip of your finger A tablespoon is about the size of an ice cube 1/4 cup is about the size of a large egg 1/2 cup is about the size of a tennis ball A full cup is about the size of a baseball, an apple or a fist Ideally, you would use your hands as they can be cupped to create a rounded shape. However, this may not be appropriate for sticky liquids. Try to select a transparent vessel that you can easily imagine your visual aid just fitting into. For example, if you are measuring a 1/4 cup, it may be useful to use a tall glass that an egg would just fit into. A wider glass, on the other hand, may be more appropriate for a 1/2 or full cup. This will help you to clearly see the amount being poured. Pour the fluid slowly into your vessel. When you think you may have the right amount, stop and compare it to the size of your visual aid. Make adjustments to the amount in the vessel if necessary. This will make future estimations easier, as it provides you with a point of reference. It is helpful to continue using the same vessels for the certain measurements (e.g. the tall glass again for a 1/4 cup).
Use an object as a reference point. Choose an appropriate vessel to pour your liquid into. Place your vessel on a flat surface and bring yourself down to eye level. Take a look at the amount of fluid in the vessel and commit it to memory.