Applying Stain– Old School
Here’s an exhausting hobby! Rule #1, get knee pads. The trick to this is to keep your wet edge to prevent color discrepancies. In just the few moments it took to focus and snap some photos I could see dark spots. Keep in mind though–once the varathane goes on you won’t see very much color variation. 
We actually had this color custom tinted by our paint store. It was a combination of 3 different colours in an effort to closely match a pine floor adjacent.
Yes sir, Rubber Gloves, A Rag and Stain. You can use a mop head or wool pad with a broom handle to apply stain, however it will be more streaky and just not as deep and rich typically. You get residue resting on the grains unless it is hand rubbed.
It is a simple task really… apply with a rag… rub excess off with clean rag. Don’t take breaks.
Some people will tell you to use a wood conditioner, and if you are considering you may want to do samples to determine which look you like the best.