A small hard lump (like a dried pea) on the front or side of the
testicles
Anything that is abnormal for you
Pain and/or tenderness in the testicles
Blood in the sperm during ejaculation
A build up of fluid in the scrotum
Tenderness or enlargement of the breasts
A dull ache in the lower abdomen or groin
An increase, or significant decrease in the size of one testicle

If you experience any of the symptoms described, go to your GP as soon as possible.  Similar symptoms can occur in other conditions and does not necessarily mean that you have testicular cancer.

This can be carried out during or just after a shower, since the
scrotum is soft and relaxed.

Place your scrotum in the palm of your hand
Look for changes in size or weight (Remember it is common
for one testicle to be larger than the other and for one to hang
slightly lower)
Gently roll each testicle individually between your thumbs
and fingers using both hands
You may feel a soft tube at the top and back of the testicle,
this the epididymis which carries and stores the sperm. It may
be quite tender normally to the touch
Feel each testicle, each should be smooth without any lumps,
or swellings.