The most common way of editing the .htaccess file is via the hosting file manager or using a text editor on your computer and then overwriting the file afterwards. If you prefer to do everything via your WordPress admin area, you may want to consider installing the WP Htaccess Editor WordPress plugin.
Once installed, you can edit your .htaccess file directly in your admin area. This is useful if you edit your .htaccess file on a regular basis (for example, for setting up link redirects).
The plugin also has a useful backup facility. When you select the backup option it creates a copy of your .htaccess file in your wp-content folder. It also gives you the option to download the file directly to your computer. If anything goes wrong you will probably have to revert htaccess via your host file manager or directly via FTP so it’s prudent to keep a copy to save a copy on your computer as well.
There’s not really much to WP Htaccess Editor. It does exactly what it promises it will do and does it well. I don’t recommend using this unless you are very experienced with editing the htaccess file as it is a very temperamental file. For example, by placing just one character in the wrong place you can totally disable your own site. Experienced website owners will find this useful for making quick edits though. Gennady also raised a good point about this plugin being a security risk. If someone was able to gain access to your WordPress website they would be able to compromise your site as well as others on the server.
Taking these points into consideration, it was wise to always update your htaccess via FTP.
Link: WP Htaccess Editor