Outside of Key of Solomon, which I waited for others to post, there are many equally valid practices for "consecration".
Ideally, you will understand the effect and function of this consecration in the greater framework of one's practice.
Some of us make our magical tools from specific ingredients selected for their nature: there's little to bless or consecrate away and the intent of purpose and life of the thing is part of it's power anyway. Such things are consecrated by being what they are.
Some of us invoke specific rituals laid down in tomes of long tradition.
The important part is laying down your context and intent on the thing that is your pentacle and such that the weight of it bears conviction in you and strong memory of it's purpose when you look upon it.
It could as much be doing a specific ritual, and then repeating some subset of that ritual when you draw pentagrams/pentacles in the future.
Mostly, it means looking into whatever it takes for you to establish that connection to your intent, and that means you have to read books, or go and rip it out of the chaos for yourself.
Ultimately, we cannot tell you what you believe, and that's what it comes down to: what do you believe will consecrate your pentacle(s) to it's(their) purpose(s)?
The most extreme will amount to 'you will get cut, you will get burned', and the mildest will involve spending some money on some stuff; Candles make a very good, repeatable prop. The Key offers some middle ground here.
Whatever you do, if it doesn't carry sufficient weight of intent, you will have to try something else; focus on shifting gears rather than escalation unless you know you are close to the breakthrough you need.
The most important part in all this is being able to connect reliably with your intent.