Get an oral syringe without the needle part, for example one that can contain 1 ml. They are sold for giving babies and pets medicine. Then you are able to measure the volume that corresponds to the wanted dose, squirt it in your mouth and hold it under your tongue for as long as you can without swallowing what's in your mouth.
You may also squirt the solution into your nose but be careful to only do this in small parts so that it will not drip down the back of your sinuses into your throat because it is then again swallowed and basically lost since it does not work well (or hardly if at all) orally. Better to do small bits of liquid and give it a few minutes to absorb before putting in more than doing too much at once. Also check the 25C-NBOMe thread for example where people describe the volume a typical nose can tolerate without getting an excess that drips.
Squirting it up your a-hole is also an option but often not considered acceptable. I myself have plugged 2C-B in the past with success but on the other hand don't particularly feel enthoused about it. But I'm obviously not prude about it either.
So there you go, a number of options actually.
Also, if you are unable to get syringes but do have access to a scale and small vials or mini containers for holding small volumes of liquid you can weigh your solution since if it is water it will be almost exactly 1 g per 1 ml (to be exact 1.01 g if there were no cuts).
Remember! This is a very potent and relatively not well researched compound so don't start at a full active dose but test with a fraction of it first and slowly build your way up. Experiment as responsibly as you can!
Regarding the 50% dextrose cut, that sounds pretty silly. I cut my 25X-NBX compounds with mannitol myself so I actually find it a fine idea, but I use ratios like 1:40 or 1:50 because that has actual purpose. 50% is bullshit right?
P.S. about krokodil even though it seems like it was a joke or sarcasm the drug itself actually doesn't seem bad at all to me. I'm even interested in making a little for myself using a proper way instead of the unsafe methods street junkies use. Because the impurities / toxic reagents from those bad methods are actually what cause the horrible problems. Just fyi let's not forget that.