I kind of figured it out, this is my solution:

Each block you place in an area you're on count as one value, i.e Plains Blocks, Forest Blocks, Peak Blocks, and Waterside Blocks.

So depending on what pokemon you want you will need a set amount of blocks for the value, I'll use Duskull, it needs 28 peak block values in the swamp, all you need to do is place 28 peak blocks (Small Rock, Big Rock, and/or Moss Rock) which equals to 28 block values. Once you placed them, I'm not sure if they just come immediately, I left the safari game and came back in, walk around the grass and Duskull should appear, I don't know the rate for finding it but you will eventually see it, I was able to find it.

For the ones that needs to be found with 31 or more block values, this one will be tricky, since you are only able to place 30 blocks in each area.

Each block is able to upgrade, but it depends on blocks:

Day Block Upgrade
10 Plains 1
20 Forest
30 Peak
40 Waterside
50 Plains 2
60 Forest
70 Peak
80 Waterside
100 Plains 3
110 Forest
120 Peak
130 Waterside

The upgrade will only work when you place a block in an area. So, if you want a Pokemon that needs over 31 block values, i.e Dusclops, which needs 35 block values, you will have to place 18+ forest blocks in the mountain area, wait for 20 days and your blocks will be doubled to 36+, thus giving you the satisfied amount.

I was able to find a Shroomish this way (and I forgot I did it), which needed 35 forest block values and 12 plain block values.

I'm not sure if this is correct, but I think I read that you are able to pick up and keep the upgrades you have done with the same amount of block you have placed, so you are able to use it with other blocks, again, not sure if this is correct.

Hope this helps.