First, what you call paper isn't paper, it's a type of plastic! There's a possibility that it will melt if you try to transfer it using clothes iron.
Next, the document for the board doesn't mention that it's covered by anything, but if it actually is and you really want to use toner transfer, you'd need to get rid off the cover using developing solution. If you manage to get the real datasheet for the board, you should be able to get recommended solution there. I just use 10 g of NaOH in 1 l of warm water.
You also need to expose the board as well. First a quote from Wikipedia:
Photoresists are classified into two groups: positive resists and
negative resists.
A positive resist is a type of photoresist in which the portion of the photoresist that is exposed to light becomes soluble to the
photoresist developer. The portion of the photoresist that is
unexposed remains insoluble to the photoresist developer.
A negative resist is a type of photoresist in which the portion of the photoresist that is exposed to light becomes insoluble to the
photoresist developer. The unexposed portion of the photoresist is
dissolved by the photoresist developer.
You need to get documentation for your board or try your luck and determine if you need to expose it before developing or not. If you do need to expose it, just leave it in the direct sunlight for a few hours and then drop it in the developer. After it's developer, rinse it in water and the photoresist should be gone.
If the other side is not coated, I don't see a reason why it wouldn't work well for toner transfer.
After that, you need right paper, right clothes iron (or laminator) and right printer. That's why there are so many recommendations! Different combinations of those will provide different results.
I haven't experimented with magazine paper yet, but from my experience the thicker and glossier paper is, easier it will be to transfer the toner from the paper to the PCB. Also you need a good heat source to transfer the toner from the paper to the PCB.
In my experience, if you don't know what you need, go for FR4. Currently it seems to be the "default" PCB material.
Finally, since you said you don't have any resources locally and aren't in a rush, consider ordering a done PCB. It will be probably be cheaper than complete investment of making the PCB yourself.
My response is going to be the opposite to that of @NickAleeev.
I had similar questions in the past about trace current limits and here are my findings. I haven't done real world tests to confirm this (yet).
The standard for current capacity in a trace was established in a document (IPC-2221) which is what alot of online calculators use. The document is old and outdated. The new standard is the IPC-2152. The IPC-2221 is conservative, and if you can go that route it might be best too. If however, you are limited in space, then IPC-2152 would give you better results. Different calculators will give you different answers, depending on what standard they are basing it off. I have only found two calculators that use IPC-2152 and when I asked my fab house, they said that they can't tell me.
Also internal layers while they are sandwiched (in FR4) have a greater thermal conductivity than air. (The link below goes a bit more into it). They will dissipate the heat more to the surface, and if you have a solid plane between your internal layer and the outer layer, you have a pretty good sink for all that heat.
Have a look at a question I had asked in the past [what is the current limit through a trace? ] you can probably just jump to the end of the question and read the answer.
Some advice I got from this, was just build a dummy board, inject your current into a trace, and see how it reacts. All the, this table says this, that table says that, can't beat an experiment that you can test yourself.
Best Answer
When a multilayer board is produced, the copper structures of inner layers and outer layers are manufactured in a different way. If an inner layer should be 35 µm thick, the take a thin board with 35 µm copper on both sides, add fotoresist, expose thru a film with the structure, develop the resist and etch all unwanted copper away.
The outer layer are done different, because the drill wholes should be plated with copper. They use a copper foil with only 17 µm for the outer layers and add another 17 µm of copper by galvanic deposition. But all areas where you want no copper are covered with resist. The galvanic deposition of copper is done only at uncovered traces and copper planes and inside the drill holes. But you want all traces to get an equal deposit of copper. If there is a single trace in an area of the board only, all copper from the galvanic anodes goes there and this trace get much more copper than only 17 µm. At other areas of the board there may be a very dense population of traces. The copper from the anodes inside the galvanic bath spreads to all traces there and the deposition of copper will be less than 17 µm.
If the outer layers are structured with a good balance, you will get an equal deposition of copper to the whole area.
Balancing the copper is recommendable only for the outer layers of the multilayer if the inner layers are structured by pure etching.
But you should ask the board manufacturer about his recommendations for inner and outer layers.