Natural blinds work just fine and cost nothing but your time and effort, if you go with a pop-up though select a cheap one first rather than splurging on an expensive blind that you may later decide you don't like. You can always upgrade. Another thing to consider is how much weight you're prepared to pack in with you, and bow hunters also have to consider head room for their bow. Many pop-ups are far less than bow friendly, especially for trad bow hunters. If you only gun hunt try an Ameristep Outhouse™ or Doghouse™, both are light, cheap, very portable, and easy to set up. They come in a range of patterns nowadays, although I've used one in their Tangle™ pattern for over 6 years now with few negative reactions. A pop-up has several advantages over a self constructed natural blind, notably enhanced protection from the elements. Their principle disadvantage is that they don't always match the terrain you hunt, but brushing them in and being careful with your back drop can get around this.