Crochet help

[Aasia]

[inc,dc in next dc] x 6 [18] meaning

What does dc in the next dc mean. Should I do a dc into the dc I made or in the next stitch I am not sure. I'd be grateful if someone could help. Thank you 

[Maryarn]

Hi Aasia. 

So, you've completed either a row or round of dc and now you're going over that previous row. It looks like from the instructions you've posted that on the current row you've done an inc (increase), and now in the next dc stitch from the previous dc row, you will do a dc. Here's a picture - hope this helps.

[Granny Square]

What she said ^ , but there's more going on in that line --

"[inc,dc in next dc] x 6 [18]"

Inc(rease), is typically understood to mean 'put 2 stitches into 1 stitch' (some patterns may define that differently, but they should put it in the stitch definition section if so)  

as said above, and swatched, DC in next DC means 1 DC into the next DC

[ stuff ] x 6 means repeat all the stuff in the brackets 6 times, so for your pattern line it would be: inc,dc in next dc + inc,dc in next dc+ inc,dc in next dc + inc,dc in next dc + inc,dc in next dc + inc,dc in next dc

[18]  - a number at the end of a row (not always in brackets) is an optional but handy sanity check, it's the number of stitches in each row or round.  Sometimes that sanity check number might be more specific if there are different types of stitches in a  row (unlike your pattern of all DC), like "9 DC and 9 SC" for example.