Pronunciation

Vowels
Czechs have five short vowels - a, e, i-y, o, u and five long ones - á, é, í-ý, ó, ú-ů

Consonants
There are 25 consonants in Czech which are divided into hard and soft.
Hard consonants - h, ch, k, r, d, t, n.
Soft consonants - ž, š, č, ř, ď, t´, ň, c, j.
The rest are ambiguous - b, f, l, m, p, s, v, z. Which means they can be hard or soft according to their use. The letter that causes the most difficulty for foreigners and makes Czechs laugh every time you try it to pronounce it is ř. It is said to be one of the most difficult letter to pronounce in the world. It may be. The best tip is to stick your tongue to the back of your teeth and hiss shuhhh quite loudly. It is a little like a Scottish rolled "r" together with the sound "s" from leisure. This won’t work, but the Czechs will get the picture.
Some other slightly easier to pronounce letters.

The letter á - long a as in farther
The letter č - ch as in church
The letter ď - as in duty
The letter é - as the ye in yet
The letter í - as ee like in weed
The letter ň - like the ng in pang
The letter ó - like awe
The letter š - like sh in shop
The letter ť - like tu in tuna
The letter ú - like oo in soon
The letter w - like v
The letter ý - also like ee in weed
The letter ž - like the s in pleasure