First, if you don't already do that, it's better to work in a dedicated singleplayer creative game (a "blueprint factory") when you want to build a single detailed object like your sword. You need a flat world, without animals, caves, POIs... That allows you to fly, to not manage resources, and to have a quick access to blueprints in your inventory. You can also make quickly many trials and variations with blueprints. When it's done, make a blueprint of the final version and tranfer it to your main game.
Then, it's better to use widely the console commands (tod, gridsize, size, setl... and many more) to optimize the way you build. Mesuring tape is also a good tool to keep your creations in the right proportion; you can also change the measuring system (blocks / metric / imperial) with the C menu. The numbers of blocks used in small objects like this one can be quickly an issue, keep an eye on it all the time, and especially when you make a blueprint (you can read it directly at this moment).
At the end, you need to try again and again to make what you have in your mind. Familiarization with building tips is the best way to obtain the result you want, think to explore advanced building functions, especially surface editing that will help you to obtain an oval shape handle for example. But you are already in the good direction, your screenshots are already pretty nice 
Edit: Of course surface editing for an oval shape handle is a mistake, but the point stays true despite this bad example.