下载Documents文件管理应用。 打开Facebook。 前往你要保存的视频。 确认视频是公开的。 打开视频。 轻触分享。 轻触菜单里的复制链接。 打开“Documents”文件管理应用。 打开浏览器。 轻触地址栏，也就是屏幕顶端的文本框。 打开SaveFrom网站。 粘贴视频地址。 轻触下载。 轻触完成。 轻触“下载”图标。 观看视频。 将视频移动到iPhone。

Given the above summary, write a detailed text in English for it.
Open the App Store  Tap Search  Tap the search bar. Type in documents  Tap Search  Tap GET to the right of the "Documents by Readdle" heading. Enter your Touch ID or Apple ID when prompted. Press your iPhone's Home button to return to the Home Screen, then tap the Facebook app icon, which resembles a white "f" on a dark-blue background. This will open your News Feed if you're logged into your Facebook account. If you aren't logged in, enter your email address and password before proceeding. Scroll through your News Feed until you find the video that you want to save, or go to the profile of the person who shared or posted the video to find it there. If you see a globe icon below and to the right of the name of the person or page who posted the video, the video is public and you can proceed. If you see a two-person silhouette or a lock icon instead of a globe, you cannot download the video. Tap the video to begin playing it. This is important, as proceeding to the next step before playing the video may result in a broken link. You'll find this option directly below the video. A menu will appear. It's in the menu. Doing so will copy the video's address to your iPhone's clipboard.  You may have to scroll down to find this option. If you open the video from your Facebook "Saved" menu, you may not have the Copy Link option. Press your iPhone's Home button again, then tap the Documents app icon. It resembles a multicolored "D" on a white background. You may have to swipe through a tutorial before proceeding. Tap the Safari icon in the lower-right corner of the screen. You may have to swipe this icon from right to left in order to open the browser page. This is the text field at the top of the screen. Type savefrom.net into the address bar, then tap the blue Go button in your iPhone's keyboard. Tap the text field near the top of the page, tap it again once your iPhone's keyboard appears, and tap Paste in the pop-up menu. If a pop-up ad appears while you're doing this, just tap the X in the top-left corner of the...