Correct the sentences

Hi,

I have three phrase/sentences that look like in needs of corrections.

1. Try to have a reference book nearby so you can look it up.

(the usage of "so" and a possible need for a comma or two.)

2. that will be very effective in acheving your goal.

May be, "that will be very effective in your pursuit of realizing your goal."

(I don't know, how can I use the word "effective" appropriately?)

3. "in needs of corrections"? Why not, "in the needs of corrections"?