Most vloggers use the mic that's with their camera. If your camera has bad audio, you can record your voice like you would for commentaries, and match the audio with the video. It's a lot of work, but that's the only thing I can think of. Either that, or invest in a new camera. A great quality camera that's fairly inexpensive is any of the Canon Powershot ELPH series. A lot of vloggers use them (Even channels with 1-3M+ Subs). The video is good quality (720-1080p), and the audio is great. -
As for the cuts, vloggers do this to keep the viewers attention, and make their videos more professional. When you think about it, vlogging is much like public speaking. Cut out any mistakes, coughs, pauses, "ums", etc. Anything that is unnecessary, and/or distracting. Vlogs are generally pretty short, averaging 2-5 minutes. Sometimes more, sometimes less. You want to say everything you need to in the shortest time possible. Vlogging focuses all on the person talking, so if you're messing up, pausing, coughing, etc. people are going to notice, and they will get distracted from the actual video.
Some other tips for vlogging is be confident. (I haven't watched any of your videos, so I don't know how you are commentating). Sounding confident will help your videos out a lot. Talk about trending things, and be yourself. Don't be afraid to try new things, or make a fool out of yourself, or be weird. Just have fun. Be sure your lighting is good, as no one likes watching a dark video. Watch other vloggers to get an idea of how they do things, and try them out yourself. Just remember don't copy them hehe.
