Download and install Advance Downloader for Mega from here
Open and copy the link of the file found on mega cloud you want to download. (When opening the link, it will take you to play store. Close playstore and copy the link from your browser)
Launch Advance Downloader for Mega
Tap on Add Links
Tap the paste icon to paste the link
When you see a tick and a small green thumbs up, then your file is ready for download
Tap the download button at the top right
Download process will begin and you will see progress bar with download speed.
When download is complete, check your downloaded file inside Download folder of your SDcard.
If you want to learn how to download from MEGA with PC easily, click here