Flush

Generally if u hold 2 cards of the same colour on hand, and u have 2 more on the flop, making it 4 out of 5 for the flush, is it advisable to chase the last card by paying money to see the last to cards? Is that strategy profitable in the long run?

You should read about explicit and implicit odds. Its the way you should play in this cases.

I dont want to give you right now a lot of information about it but, so as to get you started:

If you know you need the flush to win the hand just call bets of aprox 1/4 of the pot.

Example:

2 People in the hand. Pot is 100$
The other bets 25$
So you have to pay 25$ for a 125$ Pot. That means that you get in risk 1 $ to win 5 $.
The probability of getting the flush is more or less 4,1/1 underdog
Now if your pot odds 5/1 is bigger than the probability 4,1/1. The call is justified. If not fold.
Why?
Because you will lose 4,1 times for a total of 102.5 $
You will win 1 time for a total of 125 $
That is a profit of 22.5 $ every 5.1 hands that you play this way.
This is a simplification of the way you should think, it is much more complicated, you should check some books about this topic.

PD1: Sorry if you dont understand anything, english is not my native language. Im also a newby player, so correct me if needed
PD2: You should have posted this in Learning poker section.

Depends on the hand. There are weak draws and strong draws. If you have some outs other than those to make a flush (like a OESD) it is profffitable to call even a shove because you chances are over 50% or you can shove yourself because when you hit it is too obvious and you won't get paid . If you do not have other outs than stick to the pott odds.

i think one thing that makes a big difference is whether you have an over-card or 2 to go along with your flush draw, that way you can hit your suit or your over(s)

if you are just flush drawing u have about 40% chance of hitting ... 2 overs and you are around 50%, so calling in that situation is almost always a solid play ... the more conservative route would be to re-raise, you might lessen your implied odds, but you can better avoid a disasterous hand

i prefer to bet my draws, trying to give myself 2 ways to win ... hit my suit or take the pot with a bet ... even if someone puts you on a flush draw, they may still fold a mid pair esp. if others still are yet to act on the flop
one very dangerous thing is to get into a pot with a small suited connector and play it passively ... you may hit the flush on the turn only to have someone have a higher flush or you can end up with another of your suit hitting the river and someone with an A or K makes a big flush to beat you

i think it all comes around full circle to playing good hands and always trying to give yourself 2 ways to win
finally, you have to consider getting yourself pot committed ... if calling the flop with a flush draw puts you in a pot committed situation, then you really have to consider your odds to be 20%, b/c that next card will mean everything .. if you miss, then you have little choice at that point and you will be comitted to putting the rest of your chips in at a long shot ... so you stack is also very important as always