First of all don't even think of going to your doctor for a prescription of genuine Viagra. The doctor will either laugh at you, or tell their secretary who from that point on will look at you funny. Another reason is that real Viagra is very expensive.
That leaves generic Viagra. There are many sources of this, and believe it or not some are actually legitimate. Do not order from an email spam though, always search the Internet for a company that at least has a professional looking website and has customer support online you can chat with.
When ordering, buy the largest pill size possible. You will save money and can later break the pill up into the amounts you require.
Most generic Viagra comes from exotic places such as the Republic of Maldives, and customs may be on alert for this. Track your parcel if possible and watch for a "Denied by customs" status. If this occurs contact your vendor and they will likely resend another package, and hopefully customs will eventually let one through.
When the nondescript palm sized parcel in brown paper eventually arrives, and your loved one asks you what it is, respond in as ambiguous a way as possible. One suggestion is "Something for you, it’s a surprise." and hope she thinks it is an early Christmas present and forgets about it.
If you ordered the largest pill size as directed above, you now need to cut it into the amounts needed. Using a butter knife is not recommended as pieces will fly across the kitchen floor only to be quickly scooped up by your Labrador Retriever. Buy a pill cutter from your local drug store. To make sure they don't figure out why, first take a red marker and make small dots up and down your arms and roll up your sleeves. The last thing you want is for the cashier to think you've got erectile dysfunction.
Cut the pill into four pieces. Take one as an experiment to make sure it’s not rat poison.
Great. Now the tricky part is timing. You need to take the pill up to an hour and half before sex. Try to read the trajectory of your loved one's attraction to you to guess if sex is possible in the next couple of hours. When the time is right take your pill.
After about 20 minutes, take a quick look in the mirror. Depending on your complexion, you may be completely beet red in the face. This will adversely affect your chances of having sex that evening. It is advised you suggest drinking a couple of romantic glasses of wine with your loved one. You now have an excuse for being so red, and/or she may no longer notice.
If all has gone well you have an exciting night of hot sex ahead of you.
The worst case scenario is you completely misread your lover’s mood and forgot that she has a Pilates class that evening. Enjoy an evening of uncomfortably walking the dog around the block and then playing Call of Duty online with 12 year olds while you have an erection.