get yourself a roll of red flooring paper from home depot or another building supply. It's typically used to protect flooring when your walking around on freshly laid floors. You can use thin cardboard for this as well but it's a little more difficult to deal with as its somewhat stiff.
This pattern making can be done with two pieces or four pieces...you make the call...I found the two piece method worked well for me.
Cut two pieces of paper the exact length of the area your covering and 20" wide The two pieces should overlap at the center by some 6-10 inches....not a critical distance. You'll be trimming the edges to match the cabinets and any offsets of your particular camper.
Fit the first piece to one side of the campers offsets with a utility knife or pen and scissors...either one works, roll it up and place it aside. Lay out the second piece and trim it to the irregularities of the second side. Remember you'll be flooring under the refer or ice box...so continue the paper under and in that location a couple inches so your seam will be hidden. Once you have the two pieces trimmed to fit their separate sides place one piece down tight to the trimmed side, then place the second piece down tight to the second side. The two pieces should overlap in the center. Very carefully, with small pieces of blue masking tape, tape the two pieces together at their seam in the center of the floor. Check the fit on both sides...you should have the paper trimmed to the exact edge of the existing floor...If it's off slightly...remove the blue tape pieces and adjust to fit or trim with the knife.
Now you have a pattern of the flooring, in red paper. Taped together at the center.
Remove your pattern from the camper, turn it over, lay it on a flat surface and tape the opposite side. Tape both sides completely end to end. If you want to check your pattern..insert it in the camper and recheck the fit...I'm a "measure twice/cut once" kinda guy...so I checked my pattern for fit...adjust accordingly.
Now you can use the red paper pattern to lay on your flooring and cut it....carefully....to size. Tape the pattern down with small pieces of tape around the edge to hold it flat and trace the pattern with a fine point sharpie felt pen. take into consideration the pattern of the flooring...some have tile patterns and you will want to balance the visible tiles or pattern on each side....do this before you tape and trace.
Some campers have a bead around the vinyl flooring...if you can....trim your new flooring to fit to the bead...if its damaged badly, remove it. You can apply a 1/4 round vinyl trim after the flooring has been installed...or a piece of short cove base. (it hides mis-cuts too)
Use the appropriate adhesive for the flooring you have selected...make sure its appropriate for using directly over vinyl flooring...some are used specifically for use over new underlayment.
Once you have your flooring cut and ready to install...install with the appropriate adhesive and a notched trowel...see the adhesive container for the appropriate size of notched trowel for the adhesive you're spreading.I use 1/8" notched trowel square or grooved, each work. I layed the flooring in the camper dry on a test run and marked the location of the piece under the refer...and marked the floor with a sharpie. Only apply glue to the edge of the area where the flooring is going to be applied. Finish the other piece if you choose, tomorrow when the first piece is dried in place.
I spread the adhesive on the floor over the top of the existing vinyl...making sure you apply enough to reach all the edges....move the adhesive around with the trowel so you have even coverage of the adhesive.
Now comes the tricky part.....holding the vinyl piece you have so carefully cut in front of you, with the finished surface facing you, slightly pull the sides of the vinyl piece together forming a horseshoe....the curve facing out, away from you. If you did this on a dry run it's easy. Step up to the entrance of the camper and very carefully lay the center of the curved vinyl down as close to the center and as far forward as you can reach...preferably all the way to the small drawer under the table....BTW...the table should be out
Lay the material down to one side of the camper and slide to the edge ( you shouldn't have to slide but an inch if that). Using the heel of your hand smooth the flooring material down well enough to hold it in place...then lay the opposite side down and move the flooring into its final position. There is always a small adjustment and the material moves easily at this point.
You'll need some sort of roller to evenly roll the flooring, which compresses the glue and evens the top of the vinyl. an old rolling pin, a piece of a large dowel, a 8-12" piece of 2" abs or pvc plumbing pipe...anything to roll it out smooth.
Once the material is rolled out smooth and the edges are down tight...you will need to weight the flooring for a day or so...for a small piece such as this it will tend to curl so the weights hold it in place and down tight to the substrate. I used a few boards, cut to the length of the floor and held in place with a few bricks. Add bricks where they are necessary to hold it down tight.
Walk away once you're satisfied it's down and secure...and don't come back till tomorrow.
Once it's dried and secure....you can attack the baseboard or 1/4 round shoe if you need it. I carpeted over the vinyl and secured the carpet with velcro at its edges...so I can remove and replace the carpet without damaging the vinyl...things get dirty in the woods...but it's nice to have a soft floor underfoot.
Another thing that I found needed replacement was the thin sheet aluminum threshold at the base of the door. I removed the old and replaced it with a piece of a commercial pemko, mill finish, threshold I salvaged out of a commercial remodel a few years ago...it fit perfectly to seal the door bottom to the camper and hasn't leaked since.
Good luck...any questions...you know where to find...us
