You can let it ripe at room temperature.
If you want to slow down the ripening process, put it in the fridge, although this will affect the mango negatively.
If you want to speed up the process, put it in a bag with a banana.
When the mango is ready to eat, it will be slightly soft if you press it
and you can smell the mango flesh through the peel.
The green colour will not totally disappear.
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Fruit ripens due to exposure to a gas called ethylene.
If you want fruit to ripen faster, expose it to more ethylene.
Industrial agriculture companies often pick fruit under-ripe, ship it, then hit it with ethylene gas to ripen near the point of sale.
One common method is to put the fruit in a paper bag, which will trap the ethylene and therefore expose the fruit to it more.
If you're in a hurry, toss an apple in the bag as well.
This works for almost all fruit.
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Back home in India we had a big container filled with rice grains.
Placing the mangoes inside the container would hasten the ripening process immensely.
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Place the mango in a bowl with raw popcorn seeds.
My boyfriend is from Jalisco, Mexico, and his mother is used to ripen them in this way.
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Fruit ripening is largely caused by a plant hormone called ethylene, which is a gas.
Most fruits give off ethylene in ever increasing quantities as they ripen.
Temperature is a key determinant of chemical reaction rates and therefore, produce (fruits and vegetables) metabolic rates.
Ethylene production increases as temperature rises.
Ripening for most fruit is best at or slightly above room temperature, (68 - 70F).
Low temperature can inactivate essential enzymes required for full ripening.
The fruit may not complete the ripening processes, and/or achieve full flavor.
When detached from the growing plant fresh produce continues to transpire and lose water, therefore it is very important to maintain high relative humidity (85% RH) in the storage atmosphere.
Put fruits that emit a high concentration of ethylene such as apples, pears, bananas, avocados and passion fruit in a paper bag with slower ripening fruit, then inside a plastic bag to contain more of the ethylene gas.
Key variables affecting the storage life and eating quality of fruit and vegetables:1.
•time from harvest2.
•temperature3. •relative humidity4.
•atmosphere composition5.
•ethylene6. •pest and disease7.
•pre- and postharvest treatments
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Place in dark place, like a cabinet over night- easy.
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I've bought a fresh mango for a recipe, I've not used mango fresh before and it's currently pretty green (there didn't seem to be any that were more ripe at the shop) and came with a sticker on informatively saying just " Ripen at home ".  So, what's the best environment to help it ripen? Should it be refrigerated during ripening and/or when ripe? And how do I reliably tell when it's 'ready'?
How do I ripen a Mango?
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<ripe><mango>
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Mangoes and most other fruit ripen well at or slightly above room temperature somewhere like a dark cabinet, but you can speed this up by putting it in a bag with a banana and/or apple, or a bowl with raw popcorn seeds. To slow down the ripening process with some negative effect on the mango, put it in the fridge. Keep the fruit at room temperature. To ripen fatser, keep it with an apple or a banana.
Let the fruit ripen at room temperature. Put the mango in the fridge to slow down the ripening process. To speed up the ripening, store it with a banana or an apple or with raw popcorn seeds. Keep it in a dark place.