Most mail servers won't accept files larger than 25MB, however ours will let you send/receive up to 150MB. If the recipient server won't accept the file, then you should use OneDrive for Business. Below are the steps:
OneDrive app method
Right-click on the folder/file you wish to send, and choose Share
Un-check allow editing and optionally set an expiration
Now you can paste the URL into the body of an email.
First login to the Office 365 web portal: http://portal.office.com
Then click the app launcher at the top left, and choose OneDrive.
Next, click Upload at the top and browse for the file. Note: If you are trying to send multiple files, it might be better to first zip them and upload just the one .zip file.
From there you click the ellipses (3 dots) to the right of the file name, and choose Get a link:
Last but not least, choose the security for the link and click Copy:
You may now paste the URL, that you copied in the previous step, in an email.
Note: Anyone who has the link can access the file. So keep in mind your recipient could also share the link with someone else.