think my heads gonna blow

oil light came on went to put new oil in and my oil was all thick n mushy usually emaning thta water is getting imto the head/oil.

aint got a clue how to do a d.i.y oil change and cant afford to get it fixed just yet.

am stuck for ideas what do i do?

was the oil completely black? or was there a mayo-like substance in it?
main checkpoints i would go for first would be to look on the inside of the oil/water caps for mayo, then maybe off with the rocker-cover to check for the same stuff.
to change the oil- jack the car up at the front. you'll need a 12/13mm hex socket and a torque wrench to undo the sump plug(put a basin that'll hold 4 litres of liquid under it first tho lol) once un-done, let all the oil drain out and lower the car back down so any left over oil in awkward places will drain too. leave for 30 mins.
jack the car back up, fit the plug back in and assuming your engines the 1242cc FIRE engine fill up the engine with 3.74 litres of 10w/40 semi-sythetic oil. once that's done, lower the car back down, start the engine and leave it run for a while to build the oil pressure back up and allow it to get around the engine.

job done :wink:

And while its jacked up you can change the filter too

and that yeah