The easiest way is to upload your files to any free file sharing services (Google Drive, Dropbox, WeTransfer) and generate a shareable link.

1. Upload your files to Google/WeTransfer/Dropbox, etc.
2. Click Get shareable link. 
3. Copy and paste the link into a text file.

Then, use the Translation Project Wizard to submit a new project: 

• In Step 4, click on 'Add Files' and upload the text file you created with the link. 
• Adjust the word count manually. 
• In Step 5, add any instructions you want to share with a translator.
• Submit a project.