You can download all episodes either here at Oneddl or here at The Pirate Bay.
For The Pirate Bay you will need to use a software to download the torrent with and I recommend uTorrent which is free and can work on all operating systems. I’ve never had any problems with it but you have to be safe with which torrents you do download. It’s best to look for a torrent with a pink or green skull which means the uploader is either trusted or VIP.
I hope I explained that well and in as much detail as you might need. If not just send another message and I’ll do my best to help some more.