My background: Army Medic x 5 years, Physician Assistant 7 years - I've seen/treated a lot of wounds.

Suturing is deceptively simple - it's a relatively easy skill to learn, but takes a bit of practice to perfect. First, you really should have some training. Through training you'll discover that irrigating your wound w/ betadine, peroxide, alcohol, etc... are no-nos - all retard wound healing and damage healthy tissue to some extent. You will also learn proper closure technique - including wound prep (irrigation, debridement, local anesthetic choise & usage), suture selection, placement of sutures, types of sutures, types of knots, etc... Unfortunately, this type of training is not something you find at the local YMCA. It's typically available only to those whose professions demand the skill - physicians, nurse practitioners, PAs (in some areas "advanced practice" paramedics, and occasionally nurses - although these skills are not typically used by such)

Most wounds will heal fine w/o sutures - even very deep ones - as long as they are cared for properly - regular dressing changes, packing if necessary, etc... (again, this is covered w/ proper training).

So if wounds heal w/o sutures, why do we suture wounds? Sutures offer a few benefits:
- they produce cosmetic result (generally) than healing by secondary intention
- they restore function to torn ligaments/tendons/fascia (when used properly
- they speed the healing process in clean wounds (they decrease the degree of epithlialization, as well as contraction, needed to heal a wound)

The major pitfall, especially in traumatic wounds, where the degree of cleanliness may be questionable, is an increased risk of infection. Some infections are minor, and will be contained/eliminated by the body's immune system adequately. Some require opening the wound to allow for drainage. Some are life-threatening, and require extensive tissue debridement & antibiotics (do a search on necrotizing fasciitis - you can get a similar infection from a simple scratch).

my personal opinion - don't suture in the field - you more than likely will not be able to maintain a clean field, much less a sterile one - you are going to drag contaminated material (the suture) through the wound, innoculating it w/ bacteria (unless you have been trained in aseptic technique, and brough along a sterile drape, sterile gloves, etc..). don't use superglue in the field (it's not the same as Dermabond, either). Irrigate w/ the cleanest water available, remove any debris, irrigate again cover w/ dry dressing, monitor for signs of infection (redness, swelling, increased pain, increased temperature, drainage), seek professional care. Closure of minor lacerations may be possible w/ steri-strips or buterflies (or strips of tape, etc...) - many wounds can be closed this way, and since the skin is not artificically sealed, it can drain as needed (and if it becomes infected, you can easily remove the tape/steris/etc...

All that said, probably the best all around sutures to have would be 3-0 & 5-0 nylon (3-0, 5-0 refer to the size of the material, 3-0 being significantly larger than 5-0) on a cutting needle (sutures come on a variety of needles - cutting are used for skin, where tapered needles are used for more delicate tissues). 3-0 is fine for most parts of the body, and 5-0 would work for palces like the face, hands, etc..., where you would want to minimize the scars appearance. Really deep or long lacerations will probably require more than one layer of sutures, or something likea vertical mattress suture to close properly - again covered in formal training (or informal if you can find someone truly knowledgeable on the subject who is willing to teach you).

Stay safe