I could be fool enough at this moment to undertake any character that ever was written, from Shylock or Richard III down to the singing hero of a farce in his scarlet coat and cocked hat. I feel as if I could be anything or everything; as if I could rant and storm, or sigh, or cut capers in any tragedy or comedy in the English language. Let us be doing something. Be it only half a play, an act, a scene; what should prevent us? "Mansfield Park," Jane Austen

Lady Macbeth was refusing to read her lines unless she could have blood on her hands.

"It makes it more powerful," she insisted, and then intoned:

Here's the smell of the blood still: all the perfume of Arabia will not sweeten this little hand . . .

"See, it would be much better with the blood." And she produced a bottle of theatrical red paint and dabbed it around her knuckles.

The director gave in. It was almost 8:30 and there was a long way to go before the Birnam wood would come to Dunsinane. And until that happened, no one would get any supper.

He had been reading "Mansfield Park" and was struck by the call for the amateur theatricale -- indeed, what should prevent us? So he had planned the reading of Macbeth with a supper to follow. Being wary of the problems of casting, he had arbitrarily assigned each guest a role with their invitation -- 28 roles doubled up, with everyone being asked to read for the assorted messengers, murderers, soldiers and apparitions.

The host/director had chosen Macbeth because it allowed everyone a role or two, everyone was familiar with it from school days, paperback copies are easily attainable, if people felt inclined to make fools of themselves by wearing costumes, they could run out and buy tights. And because it provided mayhem, murder, swordplay and could be packed with atmosphere by plucking a few branches from the garden for the final battle scene.

And now here was Lady Macbeth dripping red paint all over the carpet. Like many a director before him, this one was discovering that art is not easy.

There are two ways of planning a theatrical evening. The first is to do what our host did: Choose the play and invite guests to fill the parts. Or you could decide on your guest list and then choose the play your own collection of characters inspires. You may discover that your friends are not Shakespearean at all; perhaps they are Ibsenesque, or make you think of Restoration comedies like "She Stoops to Conquer." Perhaps you move in a Pinter circle or -- woe unto you -- one better suited for enacting a Greek tragedy.

Once you have the play and the cast, decide whether everyone is to bring their own copies of the play (less expensive but riskier) or whether you are broad-pursed enough to pay. Then there is the matter of whether it will be merely a reading, with people sitting in a sedate circle putting into their voice what they are not allowed to put into action, or whether you will mount a small stage and let the actors enter and exeunt.

Scenery? Props? Costumes? Playbills (printed or photocopied) listing the cast members? The performance can be as simple or as elaborate as you choose.

Afterward there will be champagne in the Green Room and elegant tidbits like salmon and caviar (or scrambled eggs acting elegant and served, of course, with ham).

If you choose to stage a Shakespeare play and would like an impressive extra host on hand, you could produce the Bard or the Virgin Queen. The sales shop at the Folger Shakespeare Library (201 E. Capitol St., 546-2626) sells a 5-foot-tall, stuffed William Shakespeare and Queen Elizabeth ($140 each).

Or you might persuade one of your cast members to preside in a Shakespearean mask (Queen Elizabeth, Henry VIII, etc., at prices ranging from $35 to $55).

By the end of the evening, you'll know who is hammy enough to agree that acting is better than eating.