Well, 10 years of my stay in Czech Republic flew by, I applied for citizenship. I followed the document list from Ministry of Interior website, below I'll describe this list and give some comments.
0) if you studied at university or school in Czech for more than 3 years, get confirmations (make sure there's a note about Czech language!), you won't need to take exams in Czech and Czech culture. If you didn't study, long before applying (I advise about a year) take the Czech exam and culture exam, waiting time is quite substantial, total cost - about 5 thousand crowns. The process is described in detail here
1) first thing is to understand when exactly we'll have 10 years in Czech Republic. The question isn't as trivial as it seems.
Most likely the reason for your citizenship application will be that you already have permanent residence and you've been in Czech Republic for more than 10 years.
To prove these 10 years, you need to request "výpis z historie pobytu" from Ministry of Interior (come in person and request, or send a paper letter with request). In my case the document took about 2 months, price - 50 crowns per page, in my case it was 2 pages. I thought I arrived September 3rd, turned out I was registered from the 19th. I.e. if I applied before the 19th, there might have been problems.
I advise requesting this document about 2 months before potential application.
2) immediately can start preparing documents whose validity doesn't expire. First of all, certified translation of birth certificate. I did it through https://www.podebrady.ru/2012/03/15/preklady-potvrzeni/.
For translation I advise making a couple certified copies of birth certificate at "matrika" (post office may have problems with a copy of Russian language document) and give them to translator (not the original, of course). Then these copies will be bound with translation, i.e. better to make several in reserve, translation price won't change from number of copies. Price - about 500 crowns.
3) when translation is ready, can immediately fill out the citizenship application itself. I give example, note that your name and your parents' names you'll always write as the translator indicated. In my case, for example, patronymic is added: on all papers I filled out by hand, I'll need to indicate it.
4) at the same time we write a resume about ourselves (my example). Important - resume should be written as text, shouldn't be structured. Also attention to patronymics - write your own and parents'. If you don't know some information (for example, where parents live if you don't communicate with them), better to indicate this rather than ignore completely.
5) if you worked in the past, make copies of potvrzení o zaměstnání. If you work now, make regular copy of contract. Also request salary statement for last 3 years. In my case the process took about a month, i.e. do it in advance. If you're entrepreneur, again you'll have to show income for last 3 years
6) make regular copy of housing contract. If apartment is yours, then extract from cadastre
7) now about documents that can expire: need 4 documents issued no more than 30 days before application. First I advise making potvrzení o bezdlužnosti from tax office, can be done on website https://adisspr.mfcr.cz/pmd/epo/formulare, if you have data box (make one mandatory, will save tons of time). In my case I waited about 40 days for document, so I advise doing first (some of mine expired while waiting for this). Costs 100 crowns, payment instructions will be visible when applying. When you receive it, need to print at post office for 30 crowns.
8) confirmation of no debts to social security - just write to their data box (https://www.cssz.cz/kontakty), they respond within a week, free. When you receive it, need to print at post office for 30 crowns.
9) confirmation of no debts to customs. Again, through form and data box (https://www.celnisprava.cz/cz/faq/Stranky/kde-a-jak-mohu-ziskat-potvrzeni-o-bezdluznosti.aspx). They do it quickly, in a couple days, costs 100 crowns, instructions at end of form. When you receive it, need to print at post office for 30 crowns.
10) confirmation that you have no debts to insurance. In my case VZP, they'll do it at any branch in 15 minutes, i.e. I advise just coming and doing it at any free time. They can also respond to request through data box, going on foot turned out easier.
11) prepare the obvious: passport, permanent residence card
In my specific case I managed to apply on the 3rd try: first time I learned about patronymic, second time I didn't have historie pobytu yet, i.e. I tried to prove I've been here 10 years with a visa stamp, didn't work. Third time by the list above everything went OK, paid 2000 crowns (card accepted), will wait.
In any case I advise double-checking documents at matrika, since each district has its quirks.
Total cost: in my case about 3 thousand crowns with all mistakes and about 2 months of active preparation and waiting. If I took exams, would have paid about 5 thousand more.