Reading the table comes down to three habits: read a column for personality, read a row for shells, and read the number to find anything fast. Get those and you can predict how an element behaves without ever having met it.
The Three Things the Table Tells You
One — the group (column) tells you the personality. Elements in the same column behave alike because they have the same number of outer electrons, and the outer electrons do all the reacting. Two columns are worth knowing by heart. Group 1, the alkali metals (lithium, sodium, potassium…) are soft, silvery and wildly reactive — drop sodium in water and it fizzes and skates about. At the far right, Group 18, the noble gases (helium, neon, argon…) are the opposite: so content they barely react with anything, which is exactly why we fill party balloons and shop signs with them.
Two — the period (row) tells you how many electron shells. Period 1 elements have one shell of electrons; Period 2 have two; Period 3 have three, on down. So the row number is literally a count of the shells wrapped around the nucleus. Move down a group and each element has one more shell than the one above — same personality, bigger atom.
Three — the atomic number finds the element. Every tile carries its atomic number (the proton count) and the tiles run in that order, left to right, row after row. So "element number 11" isn't a guessing game — count to 11 along the order and you land on sodium, every time.
The Method for "what's This Element Like?"
When a question hands you an element and asks how it behaves, run the same three moves every time. One — find it by its number: use the atomic number to land on the right tile. Two — read its group: which column? Far left means a reactive metal, far right (bar the noble gases) means a reactive non-metal, the noble-gas column means it does almost nothing. Three — read its period: which row, so how many shells and roughly how big the atom is.
A Worked One, Slowly
Question: describe element number 19. Count along the order to 19 and you land on potassium (K). It sits in Group 1, the alkali metals — so straight away you know it's a soft, silvery, very reactive metal that reacts hard with water, just like its column-mate sodium. It sits in Period 4, so it has four electron shells, making it a bigger atom than sodium above it — and bigger alkali metals are even more reactive. Three readings — number, group, period — and you've described an element you may never have seen. That's the table doing the heavy lifting for you.