Basic things

I - Ja
You - Ti
He - On
She - Ona
It - Ono

We - Mi
You - Vi
They - Oni

Numbers - brojevi

1 - jedan
2 - dva
3 - tri
4 - četiri (Č like CHat, CHoose)
5 - pet
6 - šest (Š = sh, like SHe)
7 - sedam
8 - osam
9 - devet
10 - deset
0 - nula

11 - JEDANaest

12 - DVAnaest

13 - TRInaest

14 - ČETRnaest (this is not Četirinaest )

15 - PETnaest

16 - ŠESnaest (there is no T)

17 - SEDAMnaest

18 - OSAMnaest

19 - DEVETnaest

20 - DVA+DESET (one word - dvadeset) I'm trying to make it easier

21 - DVADESET JEDAN (or DVADESET I JEDAN)

22 - DVADESET DVA (or DVADEST I DVA)

...

30 _ TRI+DESET

40 - ČETR+DESET

50 - PE+DESET (without T)

60 - ŠEZ+DESET (not T but Z)

70 - SEDAM+DESET

80 - OSAM+DESET

90 - DEVE+DESET (without T)

100 - Sto

1000 - Hiljada (lj is one letter and in cyrillic is Љ, and it sounds something like lj together...)

1000 000 - Milion

1000 000 000 - Milijarda